Page 1 Service and Maintenance Manual BERNINA 790 PRO BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 1 of 235...
Page 2: Table Of Contents
Tools and gauges .......................... 10 Abbreviations / Names used ......................13 Cleaning and Disinfection ......................14 Technical Details of BERNINA 790 PRO ..................15 Chapter 2 - Electronics and Wiring ................16 PCBA Base – General Information ....................16 2.1.1 PCBA Base ............................
Page 3 4.3.14 Thread Take-Up Lever and Link Assembly ................. 118 4.3.15 Lower shaft ..........................120 4.3.16 Restraint-guided thrust link ......................121 4.3.17 Stitch length of crank shaft ......................123 BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 3 of 235...
Page 4 1b Machine soft- and firmware data ......................170 1c Machine Operating Time Data ......................171 1d Machine Stitch Counter Data ....................... 171 1e BSR (BERNINA Stitch Regulator) Data ....................171 1f Machine Servicing Data ........................172 BERNINA International AG Seestrasse 161...
Page 5 4b Functions of Keys and Buttons on machine ..................188 4c Start-/Stop Slide (SSU) ......................... 188 4d Foot control ............................189 4f Upper thread observer .......................... 189 4g BERNINA Stitch Regulator (BSR) ......................190 4h PCBA Position ............................190 4i Speaker ..............................192 4j USB Host Interface ..........................192 4k Basting Solenoid ...........................
Page 6 9.5.2 Measures to be taken after the Service ..................232 9.5.3 Functional check .......................... 233 9.5.4 Maintenance Checklist BERNINA 7 Series ................. 234 9.5.5 Embroidery module ........................235 Chapter 10 - Document Revision History ..............235 BERNINA International AG Seestrasse 161...
Page 7: Chapter 1 - General Information
When settings are carried out in the correct order, the machine will function flawlessly. It is important that only devices approved and distributed by BERNINA® are connected to the machine ports. When servicing or repairing, always use genuine parts and original accessories, either those delivered with the machine or purchased afterwards.
Page 8: Warning: Dangerous Voltage Levels
The capacitors require 90 seconds to discharge after the power supply has been switched off. We recommend waiting for the complete discharging of the capacitors before starting any servicing work on the PCBs. Caution! High voltage BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 8 of 235...
Page 9: Esd-Related Note: Electrostatic Discharge
4. Only use conductive ESD-capable plastic/foil pouches and ESD transport boxes for dispatching electronic components – even if the components might be faulty Video 5. To prevent consequential damage or harm, treat faulty PCBs in the same manner as new ones. BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland...
Page 10: Tools And Gauges
Tools and gauges Commercially available (not available from BERNINA): Vernier caliper, multimeter, torx screwdriver: No. 6, 8, 10 and 10 with 200 mm blade length; 15, 20 and 20 with 200 mm blade length, 25; angled torx no. 6 and 10, 10 mm ring wrench, 6 mm flat wrench.
Page 11 Helpful Tools for BERNINA machine Item no. Description Application Picture 0013565.0.00 Pinning tool short Pinning positions 0027335.0.00 Pinning tool long Pinning positions Alignment of head plate to 0315635.0.00 Eccentric key 2.0 mm the stitch plate 0079375.0.00 Pinning tool 3.0 mm...
Page 12 / Voltage tests Weight for setting the upper 0087097.2.00 Setting weight (5-pieces-set) thread tension 7304755.1.00 Distance gauge Needle bar height setting Disassembling & 0304755.1.00 Torx screwdriver reassembling aide BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 12 of 235...
Page 13: Abbreviations / Names Used
Throughout the whole manual the following abbreviations have been used. We have reserved the right not to explain individual abbreviations within the text. Abbreviations Englisch BERNINA Dual Feed BERNINA Stitch Regulator Direct Current EEPROM Electronically Erasable Programable Read Only Memory...
Page 14: Cleaning And Disinfection
Apply the liquid to a cloth and clean the surface immediately • Then use a second cloth to dry the surface • Don't forget the corresponding accessories and the power cables BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 14 of 235...
Page 15: Technical Details Of Bernina 790 Pro
Technical Details of BERNINA 790 PRO Features BERNINA 790 Technical Line voltage 100 - 240 Volt 50-60 Hz maximum power input in Watt maximum power output in Watt Eco mode (30% reduction) Total memory space in MB Overall size in mm, L-W-H...
Page 16: Chapter 2 - Electronics And Wiring
PCBA Feed Dog Drop Detection X-15 white Embroidery module WiFi X-40 black PCBA Lower Thread Observer X-104 white EMC screen connection X-42 WiFi WiFi network X-24 X-15 X-40 EEPROM BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 16 of 235...
Page 17: Pcba Cpu Module (Arm9) - General Information
Module from the old PCBA and add it to the new • Data one. Connectors • According to picture 2.2.1 PCBA CPU Module / ARM9 X-1 PCBA- Base X-28 TFT screen Contact surfaces on PCBA Base BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 17 of 235...
Page 18: Pcba Front Covers
Pattern end (S-3) o Pattern begin (S-4) • Connecting PCBA Front Cover left with PCBA RET and PCBA Front Cover right PCBA RET connector Sewing speed slide potentiometer BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 18 of 235...
Page 19: Pcba Front Cover Right
(S-3) and right needle position (S-4) • Supply for LCD backlighting • Supply for LED freearm lighting Key-function foil Connection to PCBA Base Connection to touch screen Connection to LED free arm lighting BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 19 of 235...
Page 20: Pcba Power Supply
The cause must be identified and removed. Only a replacement fuse of the correct rating must be used. It is essential to test the functions on replacing the fuse. BERNINA International AG Seestrasse 161...
Page 21: Pcba Needle Threader
Light barrier 2 receives the A/B signal of the increment disc. This signal is used for motor Light barrier 1 control, among other things • Light barrier 3 includes various positions BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 21 of 235...
Page 22: Pcba Ret
The PCBA Feed _Dog Drop Detection contains: • Light barrier • Connector • Connector • According to picture Task • Reporting feed dog status (up/lowered) to CPU via PCBA Base BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 22 of 235...
Page 23: Pcba Lower Thread Observer (Lto)
The upper and lower position of the presser foot is recognized via the light barrier. The hall sensor together with the magnetic strip determines the presser foot position. Light barrier Hall sensor BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 23 of 235...
Page 24: Sensor Support Abc (Presser Foot Recognition)
Infrared (IR) LEDs • X-38 PCBA-base Photo transistors via harness Connector • According to picture Task • Recognition of presser feet and buttonhole foot signal via sensors Sensors BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 24 of 235...
Page 25: Cable Harness
8 ABC sensor support white X 38 / / PCBA Base 9 Thread clamp white X 38 / / PCBA Base 10 Laser white X 38 / / PCBA Base BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 25 of 235...
Page 26: Bernina 7 Series Block Diagram
2.15 BERNINA 7 Series block diagram BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 26 of 235...
Page 27: Handling Of Electronic Components
Electronic components that have been manipulated or repaired by oneself are excluded from the repair/replacement process. They will be disposed of. BERNINA International AG reserves the right to charge the original price (of the new component) for electronic components that have been manipulated, repaired by oneself or improperly packaged.
Page 28: Chapter 3 - Trouble Shooting
Machine is stuck in a boot loop/ only starts up to BERNINA logo (see 3.1.9.9) Before commencing any work on the electronic side of the BERNINA Sewing Machines ensure all systems covering ESD are in place to ensure safe handling of all PCBA’s and cables. Delayed damage to prints can occur after repair if this is not done correctly.
Page 29: Information About The Three Main Pcbas
PCBA power supply to the PCBA Base or the PCBA Base is not working. Always check these indication lights for troubleshooting. Figure 1: PCBA Base, LED indication lights, top left corner BERNINA International AG Seestrasse 161 8266 Steckborn...
Page 30 3.1.3.2 Circuit board labelling Figure 2: PCBA Base, Circuit Board Type and Revision Label indicates part number – PCBA Type and the revision number as shown above in blue. BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 30 of 235...
Page 31: Pcba Cpu Module
- va374042_52370_Bernina790.bin (application) (3-Files) - vd374042_52370_Bernina790.bin (data) - xb021403_Universalbootloader.bin (bootloader) Table 1: Update files All 7-series machines have the new bootloader installed at production. Figure 3: Read the firmware version BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 31 of 235...
Page 32 Figure 5 describes the labelling location for PCBA CPU module. Rev. 0 to Rev. 4 are marked with a label and Rev. 5 is marked with laser engraving. Figure 5: Left: Labels for Rev. 0 – 4; Right: Laser engraved for Rev. 5 and later BERNINA International AG Seestrasse 161 8266 Steckborn...
Page 33: Pcba Power Supply
Make sure thread cutter button moves freely this may require removal of the button pad to be cleaned and the surrounding area of the front cover. If the error is still present it may be required to replace PCBA RET. Use service mode test 4b to test buttons. BERNINA International AG Seestrasse 161 8266 Steckborn...
Page 34 After switching on machine nothing is initialized and at the bottom left corner, written in red letters the message: “Error loading application ECC” or “Error loading application CRC” appears. Solution Force update firmware. If update fails, change PCBA CPU module BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 34 of 235...
Page 35: Troubleshooting
If the touch still doesn’t work replace it • If it still doesn’t work, replace prints bottom-up (i.e. start where the problem is and make your way to the CPU) according to the block diagram BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland...
Page 36 If the function with a new sensor is still not given and all cables are good, change PCBA CPU module and then if still faulty change PCBA Base 3.1.9.9 Machine is stuck in a boot loop/ only starts up to BERNINA logo • Check connection between PCBA Base and PCBA CPU module. Remove the PCBA CPU module, lightly blow out its slot with air and reseat (USE NO SOLVENTS TO CLEAN) •...
Page 37: Flow Charts
Please switch-off the machine and unplug the power cable before plugging in/unplugging any other cables or changing any PCBAs. Damage to the machine and/or PCBAs may occur if done otherwise. BERNINA International AG Seestrasse 161 8266 Steckborn...
Page 38 Set needle bar BDC (bottom dead center) • Switch-on (restart) machine Go to: «3.1.10.3 Not Booting to black start- booting to black SP: 5 screen with red BERNINA start screen» logo? Check all SMs in SP Go to: «3.1.10.4 Has application Application not started? starting»...
Page 39 3.Test: Try a new LCD (replace if necessary) working 4.Test: Try a new PCBA module (replace if necessary) 5.Test: Change PCBA base Return to Write a ticket «Overview» BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 39 of 235...
Page 40 Remove front cover • working Switch-on machine Both LEDs on PCBA module flashing? Switch-off machine Plug-in LCD and PCBA cover cables Return to Write a ticket «Overview» BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 40 of 235...
Page 41 4. Test: Change PCBA P-print 5. Test: Change PCBA base 6. Test: Change PCBA module All tests performed & machine still not working Return to Write a ticket «Overview» BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 41 of 235...
Page 42 Sensor ok? 4.Test: Try a new PCBA module (replace if necessary) 5.Test: Change PCBA base All tests performed & machine still not working Return to Write a ticket «Overview» BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 42 of 235...
Page 43 4. Test: Try a new PCBA module (replace if necessary) 5. Test: Replace PCBA base All tests performed & machine still not working Return to Write a ticket «Overview» BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 43 of 235...
Page 44 7. Test: Replace PCBA base Switch-on machine SP: 4c Check SS slider in SP SS slider working? All tests performed & machine still not working Return to Write a ticket «Overview» BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 44 of 235...
Page 45 6.Test: Try a new PCBA module (replace if necessary) 7.Test: Replace PCBA base Check relevant button in SP: 4b All tests Is button performed & working? machine still not working Return to Write a ticket «Overview» BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 45 of 235...
Page 46 3. Test: Exposed metal (wires) 2. Test: Replace PCBA base 4. Test: Replace SM All tests performed & machine still not working Return to Write a ticket «Overview» BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 46 of 235...
Page 47 Press F/C (more than 5s) «gears» Make sure there is no bind message on (e.g. cutter stuck) screen? All tests performed & machine still not working Return to Write a ticket «Overview» BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 47 of 235...
Page 48 2. Test: Try a new PCBA module (replace if necessary) 3. Test: Change PCBA base All tests performed & machine still not working Return to «Overview» Write a ticket BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 48 of 235...
Page 49 3. Test: Try changing PCBA module (replace if necessary) 4. Test: Replace PCBA base All tests performed & machine still not working Write a ticket Return to «Overview» BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 49 of 235...
Page 50 4. Change PCBA needle threader machine still not 5. Test: Try a new PCBA module (replace if working necessary) 6. Replace PCBA base Return to «Overview» Write a ticket BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 50 of 235...
Page 51 USB and then read it from the USB Test successful? A)with a BERNINA USB stick 1. Test: Try another BERNINA USB stick 2. Test: Check USB host port on the Read and write machine (USB A port) 3. Test: Replace PCBA-Base SP: 4g &...
Page 52: Thread Cutter And Automatic Needle Threader
The distance between the thread catcher and thread guide plate is not correct Solution • Check the installation of the stitch plate carrier with integrated thread cutting unit (see 4.3.2) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 52 of 235...
Page 53: Needle Threader Is Stoffed With Lint
Press the needle threader down and keep pressed ▪ Carefully turn the needle threader to the left as far as it will go and release it ▪ Confirm the message BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 53 of 235...
Page 54: Excessive Sources Of Noise
Check the thread path for residual threads, remove residual threads and other dirt o Check the thread path for technical defects, replace the identified parts o Carry out appropriate setting as described in the Service Manual BERNINA International AG Seestrasse 161 8266 Steckborn...
Page 55: Thread Observer
The brake spring is not correctly inserted in the bobbin case. A full bobbin must be lifted from the bobbin case around the wall thickness of the bobbin • The reflectors of the bobbin are damaged and the bobbin thread indicator detects no more movement BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland...
Page 56: Alternative Access To Touchscreen Calibration
• Access is achieved by simultaneously pressing the needle position keys and switching the machine on • The touch screen can now be calibrated as per instructions above BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 56 of 235...
Page 57: Eeprom Is Missing Or Is Incorrectly Programmed
PCBA Base under certain circumstances Solution Insert the EEPROM correctly as described in the service manual, replace the EEPROM and possibly the PCBA Base. BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 57 of 235...
Page 58: Pop-Up Messages Upon Starting The Machine In Customer Mode
The automatic thread cutter (on thread catcher) needs to be cleaned (see also SP Solution • Carry out cleaning based on the instruction on the screen • Cleaning the stitch plate carrier for technicians (see 4.3.2.1) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 58 of 235...
Page 59: Machine Requires Maintenance
• Reset the counter 3.7.3 Machine requires maintenance Message • It is time for regular maintenance. Please contact your specialized BERNINA dealer to make an appointment (see also SP Solution • Carry out maintenance on the machine • Reset the counter 3.7.4 Error message even though embroidery module is connected...
Page 60: Update Failed
USB memory. level of the USB memory (root No valid updates on USB stick directory). Defective or incompatible USB Use a BERNINA USB stick. stick Check functioning of USB stick on a PC. Is the USB stick connected?
Page 61: Other Reasons For Faulty Fw Update
Case 1: Boot loader too old Generally happens on machines from earlier production, or after some updates have been skipped. Update process can be started normally Upon starting, the black screen with the red BERNINA logo freezes or keeps appearing Solution •...
Page 62: Case 3: Machine Repeatedly Requests An Fw Update
Insert USB stick with the right FW for the machine • Switch on machine, the FW update process starts automatically • A restart after the update must be manually carried out BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 62 of 235...
Page 63: Sewing-Off Guideline
Is the stitch formation on both sides of the fabric regular? • Do the threads interlock in the middle of the fabric? • Is the seam free of skipped stitches? • BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 63 of 235...
Page 64: Zigzag Stitch (Default Settings)
Is the interlocking of the needle thread and bobbin thread on the wrong side of the fabric regular? • Does no puckering occur? • Is the seam free of skipped stitches? BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 64 of 235...
Page 65: Honeycomb Stitch (Default Settings)
3. Honeycomb stitch or leaf pattern default settings 4. Decorative stitch (401) in max. stitch width 5. Neatening of fabric edge with zigzag stitch width 3.0 stitch length 1.0 BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 65 of 235...
Page 66: Standard Buttonhole (Default Settings, Max. Length 20.0 Mm)
Does the bobbin thread show on the right side of the fabric? It shouldn’t. • Does no puckering occur? (With thin fabrics, a stabilizer must be used). • Is the seam free of skipped stitches? BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 66 of 235...
Page 67: Chapter 4 - Removal And Refitting Of Components
• Refit screw a (T20 M4x20) Due to the newly introduced thread clamp on the B 790 PRO, the head covers cannot be interchanged with each other anymore. The head cover of the B 790 PRO features an additional recess in the area of the thread clamp.
Page 68: Rear Cover
• Press cover down into the locks • Screw in screw b (T20 M4x66) • Refit the four screws a (T20 M4x16) • Refit screw b (T20 M4x66) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 68 of 235...
Page 69: Front Cover
Reattach front cover, taking care not to pinch any cables in the duct • Insert cover bottom into base plate, ensuring that the belt cover latches sit properly • Refit and retighten screws c BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 69 of 235...
Page 70: Free Arm Cover
Press the Free Arm Cover slightly up, so that it abuts the free arm cover • Tighten screw e (T10 M4x8) • Refit and retighten two screws (f) (T15) • Attach lower thread observer (see 4.2.20) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 70 of 235...
Page 71: Free Arm Cover Plate
Refit and retighten screw b • Attach the Free Arm Cover and bobbin door Take care not to interfere with the lower-thread observer wires to avoid damaging them. BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 71 of 235...
Page 72: Base Plate Cover
Secure belt cover with two screws a (T10) on fixing plate • Tilt machine to refit fastening screw b (T20) on base plate underside • Refit handwheel 1 onto upper shaft BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 72 of 235...
Page 73: Electronics And Sensors
Reconnect PCBA Front Covers with the ribbon cable • Replug PCBA RET/PCBA Front Cover left • Refit button (marked with a yellow arrow in the upper picture) • Attach the covers (see 4.1) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 73 of 235...
Page 74: Stitch-Length And Stitch-Width Adjusting Knobs
Tighten right screw 3 (T20) to fasten the bobbin winder unit, ensuring that the bobbin winder spindle will not touch the cover • Rewind the winder wires around wire harness 2. Then reconnect PCBA Base plug 1 (see 5.14) • Attach the covers (see 4.1) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 74 of 235...
Page 75: Winder Motor
Remove winder unit (see 4.2.3) Replace entirely if necessary. Assembly • Refit complete winder unit (see 4.2.3) • Functional check (see 5.14) • Attach the covers (see 4.1) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 75 of 235...
Page 76: Lc Display / Touchscreen
Stick self-adhesive copper foil tape over the severed copper foil to bridge the cut • Attach front right and front left PCBA cover to front cover (see 4.2.1) • Attach the covers (see 4.1) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 76 of 235...
Page 77: Pcba Ret/Rubber Key Pad/Ribbon Cable
Reposition PCBA RET c and bridge b properly and slightly tighten 4 fastening screws 1 • Reconnect PCBA RET c ribbon cable a to front left PCBA Cover • Attach the covers (see 4.1) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 77 of 235...
Page 78: Pcba Base
Retighten three screws a • Reconnect all plugs (note the color coding, see next page) Ensure that no wires are within the FHS light barrier area 3 Is the EEPROM attached? BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 78 of 235...
Page 79 * For connector details see 2.18 cable harness LED 5 V LED 36 V X-1701 X-1700 X-1702 X-1503 X-17 X-3112 X-3111 X-38 X-30 X-104 X-2111 WiFi X-42 X-24 X-15 X-40 EEPROM BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 79 of 235...
Page 80: Pcba Cpu Module
The current state of the firmware must be checked after assembly of the new PCBA CPU Module. If it is not the latest version, the firmware must be updated (via updating procedure). BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland...
Page 81: Eeprom (Electrically Erasable Programmable Read-Only Memory)
Video • Attach EEPROM 2 to base • Note the installation position (markings must match) and do not bend the contact feet EEPROM fitting position Markings must match. BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 81 of 235...
Page 82: Free Arm Led Sewing Light
(see 4.1) Risk of short circuit: To avoid the risk of a short circuit, attach a strip of electrical insulation tape to the bottom of the stand of the machine. BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 82 of 235...
Page 83: Pcba Power Supply With Housing
Refit the housing of PCBA 1 and air duct 2, taking care not to interfere with the main switch and power plug • Attach the covers (see 4.1) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 83 of 235...
Page 84: Pcba Power Supply
Tighten the 3 fastening screws a (T10) to secure PCBA Power Supply in the housing • Refit PCBA Power Supply and housing (see 4.2.10) • Attach the covers (see 4.1) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 84 of 235...
Page 85: Head Frame Led Sewing Light
• Fit the left LED sewing light into the socket and use small screwdriver (T10) 0304755.0.00 to tighten the fastening screw 1 • Attach the covers (see 4.1) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 85 of 235...
Page 86: Overlift Presser Food Switch (Presser Foot Height Sensor)
Some 7 Series models have no magnetic strip and hall sensor. In that case the presser-foot height sensor 4 must positioned exactly in the centre of the rear actuating lug and secured with screw 3 max 1.6mm BERNINA International AG Seestrasse 161 8266 Steckborn...
Page 87: Pcba Needle Threader
• Start machine in Service Program, select (test • Carry out presser foot height calibration • (Select test 6c), carry out buttonhole calibration BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 87 of 235...
Page 88: Pcba Dual-Feed Sensor
Video • Lower dual feed • Position PCBA BSR and Accessories Connection 7 • Retighten two screws a • Reconnect plug 8 • Attach the covers (see 4.1) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 88 of 235...
Page 89: Embroidery Module Interface
Secure on base plate with angled torx (T8) PCBA EMB connection • PCBA EMB is float-mounted. • Replug PCBA EMB connector • Attach base plate cover (see 4.1.6) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 89 of 235...
Page 90: Pcba Lower Thread Observer
Click lower thread observer a into place on hook race cover holder c shaft b (fig. 1) • Insert guiding pin on the left of the lower-thread observer into guiding rail (red circle, fig. 1) • Close the bobbin door BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 90 of 235...
Page 91: Mechanical Components
Disassembly of Hook Guideway • Remove the three screws 2 (T20) from the Hook Guideway • Carefully remove the Hook Guideway Take care not to lose the calotte washers. BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 91 of 235...
Page 92 • Tighten screws 4, remove feed dog height gage 398024.03.1+ and setting gage 3 • Continue with the assembly of the hook driver 398024.03.1+ BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 92 of 235...
Page 93 Check: The mark on the white plastic belt wheel must be exactly flush with the freearm frame lug mark. • Hook in tension spring connector between 5 clutch carriage and belt tensioner BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland...
Page 94 Replace hook if it is badly scratched or has a broken hook tip • Lubrication of hook according to lubrication diagram (see 7.8) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 94 of 235...
Page 95: Stitch Plate Carrier With Integrated Thread Cutter Unit
• Fix the thread cutting unit with three screws 1 (T8) Service information • Faults with the thread cutter may have different symptoms (see 3.1) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 95 of 235...
Page 96 Description Intensive use of the machine can cause the stitch plate carrier to become dirty despite regular cleaning. For this reason, we recommend regular cleaning of the stitch plate carrier by qualified BERNINA technicians. Measures taken by the service •...
Page 97 How to assemble the stitch plate carrier • Lightly lubricate the stitch plate carrier base, the thread catcher 8 with Klüber OY 100 0027797.2.01 (corrosion prevention only) • Insert the thread catcher 8 BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 97 of 235...
Page 98 (see 4.3.2) • How to replace the blade, with the stitch plate carrier mounted (see 4.3.3) Check if the assembled unit can be operated smoothly without jamming! BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 98 of 235...
Page 99: Blade Change On Mounted Thread Cutter Unit
Slip a sewing needle between the first and second plate. This will make it easier to pull out the knife. At the same time it'll mark the correct position for reinsertion of the new knife BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland...
Page 100 • Close bobbin door. Then complete test 6e • Refit stitch plate, attach presser foot and insert new needle; then carry out a sewing and thread cutting test BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 100 of 235...
Page 101: Thread Tension
Remove the two screws (T20), fig. 3 • Carefully remove the whole upper thread tension unit from the rubber cushion, taking care not to remove the rubber cushion from its bore (fig. 4) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 101 of 235...
Page 102 • When done, reattach all covers • Start machine in Service Program, select (test • Carry out electronic upper thread tension adjustment BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 102 of 235...
Page 103: Mechanical Basic Setting Of The Thread Tension
Retighten upper screw of thread take-up lever cover • When done, reattach covers • Start machine in Service Program, select (test • Carry out electronic upper thread tension adjustment BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 103 of 235...
Page 104 The side measured with 9.95 mm of the distance gage 735386.50.00 must go up very easily over the tension spring BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 104 of 235...
Page 105: Clutch Carriage
Reattach connecting strap between clutch carriage and thread-cutter release lever and two screws (2) (T10) • Pin the thread catcher of the thread cutting unit with 3.0 mm pinning tool a 0079375.0.00 BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland...
Page 106 (see Service Program • Check if the solenoid on the clutch carriage is properly set (see 5.8.1) • Check the distance between the spring and clutch lever (see 5.8.4) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 106 of 235...
Page 107: Hook Driver Belt Pulley
5.2.3) • Remove setting gages • Check the setting of the lower shaft on the hook driver belt pulley (see 5.6.1) • Attach clutch carriage (see 4.3.6) 0079375.0.00 BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 107 of 235...
Page 108: Needle Bar Support
7 • Slide needle bar support 12 to front, then to the left and out of thread take-up crank • Remove support 13 behind the needle bar support BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 108 of 235...
Page 109 Refit zigzag support with screw f and spring 8 • Rehook spring 8 • Remove calibration tool 14 • Set needle distribution (see 5.4.2) • Attach the covers (see 4.1) build-in BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 109 of 235...
Page 110 Unhook leg spring 2. Then slide it up along hook bar 5 • Remove circlip 3 • Slide hook bar up a little • Remove bracket 4 • Position bobbin winder gauge a 0343705.0.00 on stitch plate BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 110 of 235...
Page 111 • Prove threader height (see 5.10.2) After changing the threader head, turn the handwheel until the threader is in its idle position again before switching on the machine BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 111 of 235...
Page 112 • Press the thread clamp slightly forward until it comes to a stop, then tighten the screw b (T10) • Plug in the cable a at the thread clamp BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 112 of 235...
Page 113: Needle Bar
Use feeler gauge 8 to press spring 3 down, then slide needle holder 5 over needle bar 7 in direction of arrow as indicated • Retighten needle height screw b • Refit needle holder screw a BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 113 of 235...
Page 114: Threader Mechanism
If a washer c is fitted under the return swivel cam 12, it is absolutely essential to refit it when reassembling the parts • Remove screw d (T10 M3x8) including thread swing cam 13 BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland...
Page 115 12 at point 11 • Centre radial clearance of driving collar 3 and tighten screw a Manually check ease of movement of threader mechanism • Refit needle bar support (see 4.3.8) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 115 of 235...
Page 116: Main Motor
Position motor back into motor bracket • Retighten screw a including u-washer and serrated washer • Refit drive belt and ventilation fan • Set belt tension (see 4.1.2) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 116 of 235...
Page 117: Dual Feed
Reconnect all plugs, lay cable in duct and close. • Refit right LED housing • Set dual feed in X-direction (see 4.6.2) • Attach the covers (see 4.1) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 117 of 235...
Page 118: Thread Take-Up Lever And Link Assembly
Do not lose the washer 32 • Disengage the needle bar coupling 33 and raise the needle bar as far as necessary so that the needle bar coupling can be removed BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 118 of 235...
Page 119 (see 5.10.1) • Set the threader head height (see 5.10.2) • Set the needle bar clamp (see 5.10.3) • Set the basting device / time of disengagement (see 5.11) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 119 of 235...
Page 120: Lower Shaft
It should now be possible to pin the lower shaft with the 3.0 mm pinning tool 007937.5.00 against the lift cam • Set belt tension between upper shaft and lower shaft (see 5.2.1) • Check loop lift (see 5.6.2) 007937.5.00 BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 120 of 235...
Page 121: Restraint-Guided Thrust Link
Loosen screw 9 (T8) of bearing pin, then remove bearing pin 14 • Pull lift-/advance 16 link out, lifting it away from you and taking care not to lose the pressure spring BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 121 of 235...
Page 122 7345625.0.00 • Mount circlip 8 • Turn handwheel and check for ease of running BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 122 of 235...
Page 123: Stitch Length Of Crank Shaft
Remove circlip e for toothed segment • Push toothed segment a to the right • Remove circlip f on the belt pulley • Extend crank shaft with small belt pulley BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 123 of 235...
Page 124 Remove pinning tools • Attach PCBA Base (see 4.2.7) • Attach the covers (see 4.1) • Start machine in Service Program, select (test • Carry out balance fine-setting 0027335.0.00 0027335.0.00 BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 124 of 235...
Page 125: Stitch Length Stepping Motor
Place 0.3 mm feeler gauge 9 under stop 7 of drive gear pinion 6 • Set stop 7 of drive gear pinion 6 against rubber buffer 8 and retighten setscrew b • Remove feeler gauge 9 • Refit stepping motor BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 125 of 235...
Page 126: Sideways-Motion Stepping Motor
Attach free arm cover, be aware of clearance from the stitch plate (see 4.1.5) • Attach Free Arm Cover (see 4.1.4) • Install the rear cover (see 4.1.2) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 126 of 235...
Page 127: Presser-Foot Pressure Stepping Motor
• Replug PCBA Needle Threader connector • Start machine in Service Program, carry out (test • Install the rear cover (see 4.1.2) • Attach head cover (see 4.1.1) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 127 of 235...
Page 128: Stitch-Width Stepping Motor
Retighten setscrew c • Complete test 5e • Remove pinning tool 6 and feeler gage 7 • Set needle distribution (see 5.4.2) • Attach the covers (see 4.1) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 128 of 235...
Page 129: Presser Foot Pressure - Toothed Rack Bearing
Position entire toothed rack bearing at rear head plate and retighten three screws a • Slide pinion 5 over shaft • Attach wheel 3 including washer and circlip 4 BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 129 of 235...
Page 130: Upper Shaft
Unhook the spring 15, with higher , from the BDF lifting link • pull force Unhook the spring 16, with lower , from the BDF thrust link BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 130 of 235...
Page 131 • Loosen the screw 26 (T25 M6x20) • Move the upper shaft to the right, making sure that the washers and synchronisation disk are neither damaged nor lost BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 131 of 235...
Page 132 Adjusting the belt tension upper shaft to base shaft (see 5.2.1) • Tighten the two screws 25 (T20 M4x10) • Attach the circlip 20 • Tighten the setscrew 21 T8 of the synchronisation disk only slightly BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 132 of 235...
Page 133 Adjusting the position of the synchronisation disc (see Test • Setting synchronisation (pinning position) of upper feed to main feed (see 5.7.5) • Refit the covers (see 4.1) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 133 of 235...
Page 134: Chapter 5 - Settings
For servicing, we recommend that you always use the accessories included with the machine or purchased specifically for the machine afterwards. These are the following: power cable, foot control, buttonhole foot, embroidery module and hoop, BSR foot, and other accessories. BERNINA International AG Seestrasse 161 8266 Steckborn...
Page 135: Belt Tensions
Loosen screw b (T20), then use setting spanner 7330197.0.00 to turn the bearing until the specified tension value has been reached. • Retighten screw b Clockwise turning --˃ Belt tension tightens BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 135 of 235...
Page 136: Drive Motor
If these markings are no longer available, the belt tensioner should be flush up to max. -1 mm under the free arm surface Setting • Loosen screw 6 • Set belt tension • Retighten screw 6 BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 136 of 235...
Page 137: Head-Frame Plate Position
Setting Video • Slightly untighten screws a (T20) • Apply angled eccentric key 0315635.0.00 at eccentric engagement bore b to position head frame plate • Retighten screws a BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 137 of 235...
Page 138: Presser-Foot Settings
Ensure that presser foot and stitch plate are parallel • Retighten screw b The presser foot height is read by the PCBA Dual feed sensor and does therefore not require mechnical setting as with previous models. BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 138 of 235...
Page 139: Presser-Foot Fixation
• Ensure that presser foot sole and stitch plate are parallel - align if required • Use 3/8-inch markings on stitch plate for reference • Retighten screw c BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 139 of 235...
Page 140: Needle Settings
It must not be used for the setting of the needle/hook 0.6 mm 0.4 mm distance. Setting of needle/hook distance (see 5.6.3) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 140 of 235...
Page 141: Needle Distribution
Retighten screw b Test • Attach Revers Pattern Foot #1D • Set to maximum stitch width • Needle mustn't touch the right or left side of the stitch plate BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 141 of 235...
Page 142: Zigzag Stitch Width Limiter
(test • Needle bar support mustn't touch the zigzag stitch width limiter a Setting Video • Loosen screw b (T10) • Position limiter a • Retighten screw b BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 142 of 235...
Page 143: Mechanical Synchronization, Hook Settings, Needle Settings
Use loop lift gage 7345717.0.01 to set loop lift (2.62 mm) (see 5.6.2) • Front view: Lower shaft should be pinnable with 3 mm pinning tool b 0079375.0.00 BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 143 of 235...
Page 144 (see 4.3.7) • Should it not be possible to pin the hook driver with pinning tool 0079375.0.00: → Check the assembly of the hook driver (see 4.3.1) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 144 of 235...
Page 145: Loop Lift
(sewing direction). The two toothed wheels must run smoothly (no play, no clamping) • Use gauge to remove clamp • Tighten second screw counterclockwise (sewing direction) • Check again and repeat setting if required BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 145 of 235...
Page 146: Needle / Hook Distance
Carefully nudge stitch plate into the required position with the aid of an angled torx (T6) • Retighten screw a (T6) We recommend to use a magnifying glass to ensure accurate setting BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 146 of 235...
Page 147: Needle Height
Lower setting of gauge required = use larger diameter Available size of Art.-No. Ø in mm identification (colour) 0326675.0.00 1,50 black (phosphated) 0326675.0.01 1,85 galvanised 0326675.0.02 2,20 Nicke-plated 0326675.0.03 2,55 black (phosphated) 0326675.0.04 2,90 galvanised BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 147 of 235...
Page 148: Feed-Dog Settings
Untighten screws c (T20) • Use eccentric key 0013617.0.00 in eccentric engagement bore d to set the lateral positioning • Retighten screw c • Remove pinning tool b BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 148 of 235...
Page 149: X-Direction Positioning Against Main Feed Dog
Without sideways motion feeding • Untighten screw c (T10) • Use eccentric key 0013617.0.00 in eccentric engagement bore d to set the lateral positioning • Retighten screw c BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 149 of 235...
Page 150: Main Feed Dog Height (0.9-1.0 Mm)
Turning clockwise > feed dog level is lowered. Turning counterclockwise > feed-dog level is lifted. • Retighten screw d (T8) and check the height using gage 3980240.3.1+ • Repeat setting if necessary BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 150 of 235...
Page 151: Main Feeding Balance - Mechanical Basic Setting
The first tooth d of drive gear b must gear into the first gap of the toothed segment e • Use spring pressure to reposition calotte bearing h to the left into the motor holding plate BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 151 of 235...
Page 152 Retighten screw g to fix drive gear b at stop c • Remove pinning tools • Refit PCBA Base • Start machine in Service Program, select (test • Carry out balance fine-setting BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 152 of 235...
Page 153: Feed Dog/Dual Feed Synchronization
• Setting Video • Loosen screw g (T10) • Move dual feed into the specified position • Retighten screw g • Remove Synchroplate and pinning tools BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 153 of 235...
Page 154: Dual Feed Balance - Basic Mechanical Setting
Turn setting screw a until the distances between the drive belt flange and the setting hub are even • Carry out BDF Balance fine setting in Service Program BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 154 of 235...
Page 155: Clutch Carriage/Thread Cutter
Attach air tube ( see 4.2.11 • Reattach free arm cover plate, free arm cover, rear cover and head cover ( see 4.1 • Test sew and test thread cutting BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 155 of 235...
Page 156: Clutch Carriage
• With the lever in this position, retighten the two screws (T10) on the connecting strap between clutch carriage and cutting unit release lever BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland...
Page 157: Timing Of Clutch Carriage
Set down setting gage 7342585.2.00 on coupling ring • Position the coupling ring at the collar of the base • Tighten the setscrew d (T8) of the coupling ring BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 157 of 235...
Page 158: Distance Between Spring And Clutch Lever
Retighten the two screws e (T8 angled torx) of the thread guide plate • Refit and retighten screw c (T8 angled torx) and nut d (open- end or ring wrench 5) on thread guide plate/thread stop BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 158 of 235...
Page 159: Synchronizing Disc
Turn synchronizing disk until signal 1 is displayed in green: Between 22.5° and 27.5° • Place synchronizing disc against circlip • Retighten screw a (not too hard) • Remove loop lift gauge BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 159 of 235...
Page 160: Needle Bar Guide And Threader Head
If needed, loosen screw c (T6) slightly • Turn needle bar guide axially only until the clutch pin couples smoothly into needle bar • Retighten screw c (T6) 0.2 mm BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 160 of 235...
Page 161: Threader Head Heigh
Use adjustment spanner 7330197.0.00 to set distance of 3.5 mm k between needle bar support and retainer clamp, then tighten screw e (T6) • Refit basting solenoid housing. For setting refer to (see 5.11) Left side view 3.5 mm BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 161 of 235...
Page 162: Needle Bar Clamp Retainer Plate
Using a small screwdriver and/or the 3981120.3.0+ spring hook, push the laser into the correct position by lateral pressure on the laser a Do not press on the laser from below to avoid damaging the laser BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland...
Page 163: Basting Device / Checking The Timing Of Disengagement
Run machine at highest speed to test basting magnet in left and right needle positions If functional test fails in one, some or all needle positions, recheck the setting of the cushioner position and the needle bar guiding and adjust as required, chapters 5.10.1 BERNINA International AG Seestrasse 161 8266 Steckborn...
Page 164: Thread Regulator
Check tension • Thread thread regulator with a 30cm long bit of thread • Attach the two thread ends to the BERNINA tension spring scales (0060385.0.00) • Slowly move the scales up • On moving the regulator spring, the tension value must be 12 – 15 g...
Page 165: Thread Tension
Add another 10 grams (2 x 5 grams), see picture 4. The gauge should move down very slowly. If required, set using the multifunction knob a • Touch to save the setting • The "Successful" message appears together with the tension settings BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 165 of 235...
Page 166: Lower Thread Tension (Basic Setting)
Use a small screwdriver to set the lower thread tension by turning the bobbin case spring screw as appropriate. • Turn screw counterclockwise (to left) to slacken • Turn screw clockwise (to right) to tighten • BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 166 of 235...
Page 167: Winder
If the lower thread observer does not work flawlessly, check the state of the bobbin, especially the inner and outer reflectors on the bobbin. If the bobbin is in mint condition, replace the lower-thread indicator unit BERNINA International AG Seestrasse 161 8266 Steckborn...
Page 168: Chapter 6 - Service Program
4 = Area: Signals 5 = Area: Motors 6 = Area: Settings 7 = Area: Embroidery 8 = Area WiFi module (Technician network) 11 = Area: Final check BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 168 of 235...
Page 169 Selecting a keyboard a: Upper case letters b: Lower case letters c: Numbers, special characters and punctuation marks d: Special marks BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 169 of 235...
Page 170: Menu 1 - Service Information
Menu 1 – Service Information Machine basic data Machine soft- and firmware data Machine operating time data Machine stitch counter data BSR (BERNINA Stitch Regulator) data stitch counter Machine Servicing Data Saving customer data Customer data Dealer data Log data...
Page 171: Machine Operating Time Data
Total number of stitches using BSR • Total number of embroidery stitches • Stitches since last lubrication • Stitches since last service 1e BSR (BERNINA Stitch Regulator) Data What to test The BSR foot must be attached and connected. • Serial Number • Chassis Number •...
Page 172: Machine Servicing Data
Remember to always reset the counter (cleaning interval) after servicing or repairing Service interval • Message for customer: “Please contact your specialized BERNINA dealer to make an appointment” Reset • Remember to always reset the counter (cleaning interval) after servicing or repairing...
Page 173: Saving Customer Data
• Load the Customer settings = Loading of customer data to the machine Connect BERNINA USB memory stick and select required button. Remove the stick after saving of data has been confirmed. 1h Customer data What to test •...
Page 174: Dealer Data
• Dealer data can now be entered • Dealer data can also be read and entered in .txt format from a BERNINA USB memory stick. Important: The file must be named "dealerdata.txt" (see example below) • The dealer-related data will automatically appear on the screen when a maintenance reminder is...
Page 175: Reset Thread Cutter Counter
Customer requirement: Clean thread cutter • The counter triggers a note for the customer upon 1’000 thread cuts – "The automatic thread cutter (with thread catcher) must be cleaned" (see 3.7) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 175 of 235...
Page 176: Menu 2 - Display, Buttons
LED sewing light and brightness 2a Touchscreen Calibration What to test • Touch 'Calibrate' to start the test • To calibrate the touchscreen, use the BERNINA stylus to touch the 3 crosses as required • Touch to save and return •...
Page 177: Lc Display (Screen)
White blank screen to find dirt or stains • Touch to return Repair notes • Clean LCD and touchscreen Never use alcohol, petrol, spirits or any corrosive fluids, or abrasive pastes or abrasive cleaners! BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 177 of 235...
Page 178: Rgb (Red, Green And Blue) Screen
The start / stop button will light up green or red respectively • Touch to return Repair notes • Check cables for deformation and/or wear and tear • Replace PCBA RET if any of the buttons don’t light up BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 178 of 235...
Page 179: Led's And Brightness
• Check cables for deformation and/or wear and tear • Check connectors P-38 and P-3111 on the PCBA Base • Replace the LED’s • Replace the PCBA Base BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 179 of 235...
Page 180: Menu 3 - Sensors (Mounting Locations In The Machine)
007752.50.34 (T10) in the needle bar support • If the sensor does not respond, replace the PCBA Needle Threader (see 4.2.15) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 180 of 235...
Page 181: Presser Foot Height Sensor
Incorrect reading of presser foot height! "0" will be displayed if the presser foot sits on the stitch plate in most cases. • Check the basic setting of the presser foot height in Service Program (see BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 181 of 235...
Page 182: Lower Thread Observer
Check the sensors for dust and stains • Repeat the test using a new bobbin • Check cables for deformation and/or wear and tear • Replace lower thread observer • Replace PCBA Base BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 182 of 235...
Page 183: Feed Dog Drop
Unplug PCBA Base connector ▪ Replug PCBA Base connector ▪ Attach PCBA detection in the required position and retighten fastening screw (T20) ▪ Attach the covers (see 4.1) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 183 of 235...
Page 184: Dual Feed Recognition Sensor
If the sensor does not respond, replace the PCBA dual feed sensor. ( see 4.2.17 • The support ABC sensor (presser foot recognition, see 4.2.16) might also be affected BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 184 of 235...
Page 185: Bobbin Winder Switch
• Switch off bobbin • Touch to return Repair notes • Check cables for deformation and/or wear and tear • Replace winder • Replace PCBA Base (see 4.2.7) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 185 of 235...
Page 186: Free Hand System Fhs
Check if in the area of the sensor on the PCBA Base no cables are exposed • If the signal is not activated, replace PCBA Base (see 4.2.7) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 186 of 235...
Page 187: Menu 4 - Signals
Stitch width and stitch length knob(s) Functions of keys and buttons on machine Start/stop slide (SSU) Foot control 4e PS2 interface, intended for production only Upper thread observer BERNINA stitch regulator (BSR) PCBA Position Speaker USB host interface Basting solenoid 4l Presser-foot recognition...
Page 188: Functions Of Keys And Buttons On Machine
Touch to return Repair notes • Check cables for deformation and/or wear and tear • Replace PCBA RET (see 4.2.6) • Replace PCBA Front Cover left (see 4.2.1) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 188 of 235...
Page 189: Foot Control
Check if the regulator is properly hooked and if it actuates the actuating lug • Check if the regulator spring is properly set (see 4.11) • Replace PCBA RET (see 4.2.6) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 189 of 235...
Page 190: Bernina Stitch Regulator (Bsr)
4g BERNINA Stitch Regulator (BSR) What to test • Attach BSR foot • Select test 4g • Lower presser foot • Press the icon to start the test • Place fabric under the presser foot • Move the fabric in different directions •...
Page 191 Turn synchronizing disk until signal 1 blanks • Position: between 25° and 27,5° • Retighten screw a slightly Attention! Don't tighten screw a of synchronizing disk too tight. BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 191 of 235...
Page 192: Speaker
If 'Test Failed' message appears • Repeat the test using another USB cable • Check the client and host ports on the machine • Replace PCBA Base (see 4.2.7) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 192 of 235...
Page 193: Basting Solenoid
'Successful' appears • Touch to return Repair notes • Check plugs and cables for deformation and/or wear and tear • Replace basting solenoid • Replace PCBA Base (see 4.2.7) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 193 of 235...
Page 194: Presser-Foot Recognition
For example Feet 1C, 20C, 40C 5.5 mm feet e.g.: Feet 2A, 5, 16, 18 Straight stitch foot Darning foot e.g.: Feet 13, 35, 38, 43, 53 5.5 mm Dual feed foot BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 194 of 235...
Page 195 Press the presser foot indicator (marked in red) at top left • The currently attached presser foot will be displayed in the box top left, along with all other feet on further 6 pages BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland...
Page 196: Bsr Foot Interface
Check the opening of the laser housing to see if it is blocked with dirt or lint • Check cables and connections • Try another laser • Replace the laser or the needle bar support (see 4.3.8) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 196 of 235...
Page 197: Clamping Magnet
Check if the solenoid on the clutch carriage is properly set (see 5.8.1) • Check cables for deformation and/or wear and tear • Completely replace clutch carriage (see 4.3.6) • Replace PCBA Base (see 4.2.7) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 197 of 235...
Page 198: Menu 5 - Stepping Motors (Mounting Locations In The Machine)
Swap connectors with the presser-foot pressure stepping motor to check if the fault is with the motor or the PCBA Base Disconnect from the power supply. Do not disconnect or reconnect when the machine is powered. BERNINA International AG Seestrasse 161 8266 Steckborn...
Page 199: Presser Foot Pressure Stepping Motor
Disconnect from the power supply. Do not disconnect or reconnect when the machine is powered. Do not use the stitch length or dual feed stepping motors for testing, as these run with higher electricity BERNINA International AG Seestrasse 161 8266 Steckborn...
Page 200: Pinning Positions Of All Stepping Motors
Repair notes • Check plugs and cables for deformation and/or wear and tear • Replace PCBA Base (see 4.2.7) • Replace the winder motor (see 4.2.4) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 200 of 235...
Page 201: Stitch Length Stepping Motor
Replace PCBA Base (see 4.2.7) • Replace stitch length stepping motor (see 4.3.18) Disconnect from the power supply. Do not disconnect or reconnect when the machine is powered. BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 201 of 235...
Page 202: Sideways Motion Stepping Motor
Swap connectors with the stitch length stepping motor to check if the fault is with the motor or the PCBA Base Disconnect from the power supply. Do not remove or refit anything when the machine is powered. BERNINA International AG Seestrasse 161 8266 Steckborn...
Page 203: Menu 6 - Settings
In order to ensure the carrying out of all crucial settings and calibrations, follow the check list in menu 11 Do not run a threaded machine without fabric! BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 203 of 235...
Page 204: Electronic Balance
The basic value is 0, the setting ranges from +4 to -4 • Touch to save and return Information on correction direction • button = forward, button = backward BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 204 of 235...
Page 205 The number 9 must be sewn closed What to set • Turn balance cam a (T10) to set until the 9 is stitched properly Turn CW Turn CCW BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 205 of 235...
Page 206 Information on correction direction • Rotate the balance cam a clockwise = the leaf pattern pulls together • Rotate the balance cam a anticlockwise = the leaf pattern pulls apart  BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 206 of 235...
Page 207 Press the start button and the machine will automatically sew the pattern backwards • The difference in length between the two stitch rows should not be larger than 7.0 mm BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 207 of 235...
Page 208 Turning setting screw a counterclockwise will shorten the left side of the diamond stitch pattern while the right side of the diamond pattern will be lengthened (see 4.6.4)  BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 208 of 235...
Page 209: Buttonhole Calibration
• Replace presser foot • Check plugs and cables for deformation and/or wear and tear • Replace sensor carrier ABC (see 4.2.16) • Replace PCBA Base (see 4.2.7) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 209 of 235...
Page 210: Thread Cutter Cutting Process
Move to needle stop position up. Restore thread tension 220° Test done After setting the thread tension 220° • The message "After setting the thread tension" appears • Touch to return BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 210 of 235...
Page 211: Upper Thread Tension Reset To Default
6 • If 'No', press to return to menu 6. The tension values remain unchanged BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 211 of 235...
Page 212: Resetting To Factory Settings (Reset All)
If 'No', press to return to menu 6. The sewing settings remain unchanged IMPORTANT: It is essential to save all the customer's data on a BERNINA USB data stick before resetting to factory settings. Saving customer data (see test 1g).
Page 213: Automatic Threading Process
• Select the setting thread to be used (DMC 50, Belfil, Mettler or Amann) • A 'Successful!' message will appear on successfully completed setting • Touch to return BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 213 of 235...
Page 214: Start-/Stop Unit (Ssu) Slide Control Calibration
Repair notes • Check slider for dust or dirt and smooth mechanical running • Replace PCBA Front Cover (see 4.2.1) • Replace PCBA Base (see 4.2.7) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 214 of 235...
Page 215: Bsr Foot Sewing Program
The noise level of the machine can be evaluated • Touch to return Repair notes • Lubricate hook (see 7.1.8) • Check positioning of the Hook Guideway (see 4.3.1) BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 215 of 235...
Page 216: Thread Length Adjustment After Cut
1 step modifies the length for approx. 7.0 mm • After the adjustment, sew at least 3 times to confirm the result + 5 mm / - 10 mm BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 216 of 235...
Page 217 The stitch plate support with lower clamp is mounted in the machine (see picture, the gold-colored sheet metal clamp). • Upper or lower thread tension not ok • Clamping magnet does not work correctly, either electrically or mechanically BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 217 of 235...
Page 218: Menu 7 - Embroidery Module (Emb)
A smartphone with access to the mobile network and a hot spot function Recommended To compare the reception quality, use another WiFi-compatible device with reception strength display. This helps to assess the reception sensitivity of the WiFi module in the machine. BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland...
Page 219 4.2.7) • If additional functions are not working properly, continue by troubleshooting the other functions. Cables may also be incorrectly plugged in or the power supply may not be working properly BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 219 of 235...
Page 220: Menu 11 - Check-Out
Cleaning and servicing intervals, test After completion and confirmation of the last test with , the check-out program will return to the main menu in the Service Program. BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 220 of 235...
Page 221: Chapter 7 - Lubrication Diagram
Chapter 7 - Lubrication diagram = Klüber OY 100 (0027797.2.01) = Velocite 6 (0335675.0.01) = Klübersynth UH1 14-1600 (0027797.3.02) = Klübersynth GE 14-151 (0363327.0.10) 7.1.1 Head frame 7.1.2 Main feed dog BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 221 of 235...
Page 222: Threader Mechanism / Needle Drive
7.1.3 Threader mechanism / Needle drive BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 222 of 235...
Page 223: Toothed-Segment Needle-Bar Support
7.1.4 Toothed-segment needle-bar support 7.1.5 Upper Thread Tension Unit BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 223 of 235...
Page 224: Dual Feed Crank Shaft
7.1.7 Dual feed lift cam and feed cam upper shaft 7.1.8 Hook/hook driver Hook driver • Hook drivers with plastic housing are maintenance-free and should not be relubricated BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 224 of 235...
Page 225: Thread Cutting Unit / Feed-Dog Fork
7.1.9 Thread cutting unit / Feed-dog fork BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 225 of 235...
Page 226: Lower Shaft/Lift Cam And Feed Cam Of Main Feed Dog
7.1.10 Lower shaft/lift cam and feed cam of main feed dog 7.1.11 Feed-dog crank shaft BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 226 of 235...
Page 227: Chapter 8 - Firmware Update
The USB stick must be FAT32-formatted, so that the firmware update can be correctly ended. 1. Save the update files to a BERNINA USB stick (> 512 MB) https://iportal.bernina.com/ For BERNINA dealers www.bernina.com/downloads...
Page 228: Alternative Update Process
This starts the update process with the data check on the USB stick On completion of the manual update procedure, the machine must be started manually. BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland...
Page 229: Chapter 9 - Maintenance Guidelines
• Defined wear-and-tear parts are subject to a charge; the parts declared in the spare-parts-warranty extension (Bernina warranty provision) are excepted • Compliance with maintenance intervals allows system functioning to be ensured and increases the service life of the machines •...
Page 230: Wear-And-Tear-Parts Definition
In the case of intensive use for which the machine was not designed, increased wear and tear of parts cannot be ruled out • In order to ensure continuously defect-free operation of the machine, BERNINA recommends replacing the parts according to the table (9.4.2) once the tenth maintenance interval is reached •...
Page 231: Operating-Time-Related Parts
Machine connection The X in the 8th position of the article numbers serves as a placeholder for the modification indicator (a number from 0-9). The change sequence is displayed with ascending figures BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland...
Page 232: Maintenance Checklist
• Read out the stitch and hour counter and enter on the Service Report Customer data backup Service Program 1g. Connect BERNINA USB memory stick and select required button. Remove stick after confirmation by the machine. • Save the customer settings = Customer data saved onto the storage medium •...
Page 233: Functional Check
• Thread take-up crank • Needle bar support/needle bar Mechanical quality of the machine • Hook driver bearing • Bevel gears • Bobbin carrier / hook • Drive belt tensions BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 233 of 235...
Page 234: Maintenance Checklist Bernina 7 Series
9.5.4 Maintenance Checklist BERNINA 7 Series Front and rear cover Covers to be removed Free Arm Cover Stitch plate Hook Parts that must be disassembled or removed Bobbin carrier Recommended parts according to Tear-and-Wear Parts Definition Free-arm area Needle bar/needle bar support...
Page 235: Embroidery Module
Final check Is the set of accessories complete? Chapter 10 - Document Revision History Date Version Description Author July 2023 First edition After Sales Service BERNINA International AG BERNINA International AG Seestrasse 161 8266 Steckborn Switzerland Page 235 of 235...

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