Dell S2725HS Service Manual

Exploded view diagram with list of items

NOTE:
For replacement of power cord, connectivity cable and external power supply (if applicable), contact Dell:

1. Go to https://www.dell.com/support.
2. Verify your country or region in the Choose A Country/Region drop-down menu at the bottom-right corner of the page.
3. Click Contact Us next to the country drop down.
4. Select the appropriate service or support link based on your need.
5. Choose the method of contacting Dell that is convenient for you.

Wiring Connectivity Diagram

How to connect and disconnect power cable/ connectivity cable

To change power cable/connectivity cable, switch off power before unplugging the cable and replugging in required cable.

Connecting the HDMI cable

Disassembly and Assembly Procedures

NOTE:
This "Disassembly and Assembly Procedures" is for EMEA only, not for other regions. Please note that Dell will deem warranty void if any disassembly is done on the monitors.

Tool Required:
List the type and size of the tools that would typically can be used to disassemble the product to a point where components and materials requiring selective treatment can be removed.

Tool Description:

• Screwdriver(Phillip head) #1
• Screwdriver(Phillip head) #2
• Penknife
• Soldering iron and absorber

Disassembly Procedures

Remove the monitor stand base:

1. 1. Place a flat cushion or a sitting mat near the edge of a table and place the monitor on it with the display facing down.
   2. Press and hold the stand-release button.
   3. Lift the stand up and away from the monitor.
   
   
2. Use a Philips-head screwdriver to remove 4pcs screws for unlocking mechanisms.
   (No.1~4 screw size=M4x11; Torque=7 8kgfxcm)
   
3. Use a mylar sheet to insert the left-bottom corner to release the rear cover, then wedge your fingers to release the rear cover, then use one hand to press the middle bezel, the other hand to pull up the rear cover in order of arrow preference for unlocking mechanisms of rear cover.
   
   
4. Lift the rear cover up carefully. Disconnect the joystick cable from the connectors of the interface board, and then remove the rear cover and put it aside for later disassembling.
   
5. Use a Philips-head screwdriver to remove 2pcs screws for unlocking the joystick key board unit, then tear off the tapes and release the USB board.
   (No.1~2 screw size=M2x3.3,Torque=1±0.2kgfxcm)
   
6. Tear off 4pcs acetate tapes, then use a Philips-head screwdriver to remove 6pcs screws for unlocking the speakers, to remove 1pcs screw for unlocking IO cover, then disconnect the speakers' cable away from the connector and release the two speakers and IO cover from the hooks.
   (No.1~6 screw size=M3x8, Torque=6±1kgfxcm; No.1 screw size=M3x4, Torque=5±1kgfxcm)
   
7. Use a Philips-head screwdriver to remove 15pcs screws for unlocking the middle frame with the panel module.
   (No.1~17 screw size=M3x4, Torque=5±1kgfxcm)
   
8. Tear off 3pcs aluminum foil for releasing the bracket chassis module.
   
9. Take away the middle frame, and put it on a protective cushion.
   
10. Move up the bracket chassis module, and disconnect the LVDS cable and panel lamp cables from the connectors of the panel, then tear off the tapes and lift up the bracket chassis and put it aside for later disassembling.
    
    
11. Release the lamp cable and Mylar sheet from the hooks of the bracket chassis module.
    
12. Use a Philips-head screwdriver to remove 6pcs screws for unlocking the circuit board.
    (No. 1 screw size=M4x8, Torque=6±0.5kgfxcm; No.2~6 screw size=M3x6, Torque=6±0.5kgfxcm)
    
13. Remove the interface board and power board from the bracket chassis and disconnect all the cables.
    

Assembly Procedures

1. Place a bracket chassis base on a protective cushion. Paste 1pcs silicon sheet on the correct position of the bracket.
   
2. Take 1pcs lamp cable to connect with 1pcs power board, then turn over the power board and put it into the bracket chassis.
   
3. Take a interface board, connect 1pcs LVDS cable to the connector of the interface board, then connect the cable of the power board to the connector of the interface board. Turn over the interface board and locate it into the bracket. Use a Philips-head screwdriver to tighten 6pcs screws for locking the power board and interface board.
   (No.1~5 screw size=M3x6, Torque=6±0.5kgfxcm; No.6 screw size=M4x8, Torque=6±0.5kgfxcm)
   
4. Take a mylar to insert the hooks of the bracket to cover the power board, then locate the lamp cable into the hook of the bracket.
   
5. Panel preparation: Take out 1pcs panel LCM module from the carton, then remove the protective film by tearing off the tapes, and then examine the panel surface according to inspection criteria. Paste 1pcs dell nameplate to the front bezel of the panel module, then use a locating fixture to fix the nameplate with bezel. Turn over the panel, and then place screen faced down for later assembling.
   
6. Put the bracket chassis down on the back of the panel, then connect LVDS cable and lamp cable to the connectors of the panel module.
   
7. Take 1pcs middle frame to assemble with the panel module.
   
8. Use a fixture jip to fix the bracket chassis module with panel module, then paste 3pcs aluminum foil on the specific position to fix the bracket chassis module with panel as the picture below shown.
   
9. Use a Philips-head screwdriver to lock 17pcs screws for locking the middle frame with the panel module.
   (No.1~17 screw size=M3x4, Torque=5±1kgfxcm)
   
10. Take a pair of speakers to locate the probes of the middle frame, then connect the speaker cable to the connector of the board. Use a Philips-head screwdriver to tighten 6pcs screws for locking the speakers.
    (No.1~6 screw size=M3x8, Torque=6±1kgfxcm)
    
11. Fix the speaker's cables with 4pcs acetate tapes as the picture below shown. Take 1pcs IO cover to locate the hooks of the bracket chassis module, then use a Philips-head screwdriver to tighten 1pcs screw for locking the IO cover with bracket chassis module.
    (No.1 screw size=M3x4, Torque=5 1kgfxcm)
    
12. Take 1pcs joystick key, 1pcs joystick board and 1pcs key cable, then assemble the joystick key with board. Paste 1pcs mylar tape to cover the LED, then connect the key cable with the joystick board.
    
13. Take 1pcs rear cover, then locate the joystick board to the correct position of the rear cover, then use a Philips-head screwdriver to tighten 2pcs screws for locking the joystick board with rear cover, then fix the key cable on the rear cover with 2pcs tapes as the picture below shown.
    (No.1~2 screw size=M2x3.3,Torque=1±0.2kgfxcm)
    
14. Move the assembled rear cover close to the panel unit, then connect the joystick key cable to the connector of interface board. Put down the rear cover and push the rear cover on the positions marked as the picture below shown for mechanisms engagement.
    
15. Use a Philips-head screwdriver to tighten 4pcs screws for locking rear cover with the assembled unit.
    (No.1~4 screw size=M4x11; Torque=10 1kgfxcm)
    
16. Stick 2pcs labels on the specific positions as the picture below shown. Take 1pcs riser with cable clip, 1pcs base and 1pcs VESA cover, assemble the base and VESA cover with the riser, then rotate the screws clockwise to lock the base and VESA cover with the riser. Insert the stand-riser into monitor groove until it snaps into its place.
    Note: Please ensure the cable clip is attached to the stand before shipping out the refurbished unit from the repair station.
    
17. Lift up the monitorto checking the gap between the front bezel with panel module, then provide power supply and a video signal to the monitor, then turn on the monitor for functionality check.
    

Trouble Shooting Instructions

Before you begin any of the procedures in this section, follow the Safety instructions.

Self-test

Your monitor provides a self-test feature that allows you to check whether your monitor is functioning properly. If your monitor and computer are properly connected but the monitor screen remains dark, run the monitor self-test by performing the following steps:

1. Turn off both your computer and the monitor.
2. Unplug the video cable from the back of the computer. To ensure proper self-test operation, remove all digital and the analog cables from the back of computer.
3. Turn on the monitor.
   The floating dialog box should appear on-screen (against a black background), if the monitor cannot sense a video signal and is working correctly. While in self-test mode, the power LED remains white. Also, depending upon the selected input, one of the dialogs shown below will continuously scroll through the screen.
   
4. This message also appears during normal system operation if the video cable is disconnected or damaged.
5. Turn off your monitor and reconnect the video cable; then turn on both your computer and the monitor.
   If your monitor screen remains blank after you use the previous procedure, check your video controller and computer, because your monitor is functioning properly.

Built-in diagnostics

Your monitor has a built-in diagnostic tool that helps you determine if the screen abnormality you are experiencing is an inherent problem with your monitor, or with your computer and video card.

To run the built-in diagnostics:

1. Ensure that the screen is clean (no dust particles on the surface of the screen).
2. Select OSD items of Self-Diagnostics in Others feature.
3. Press the Joystick button to start the diagnostics. A gray screen is displayed.
4. Observe if the screen has any defects or abnormalities.
5. Toggle the joystick once again until a red screen is displayed.
6. Observe if the screen has any defects or abnormalities.
7. Repeat steps 5 and 6 until the screen displays green, blue, black, and white colors. Note any abnormalities or defects.

The test is complete when a text screen is displayed. To exit, toggle the joystick control again.
If you do not detect any screen abnormalities upon using the built-in diagnostic tool, the monitor is functioning properly. Check the video card and computer.

Common problems

The following table contains general information about common monitor problems you might encounter and the possible solutions:

Important Safety Notice

Product Announcement:
This product is certificated to meet RoHS Directive and Lead-Free produced definition. Using approved critical components only is recommended when the situation to replace defective parts. Vender assumes no liability express or implied, arising out of any unauthorized modification of design or replacing non-RoHS parts. Service providers assume all liability.

Qualified Repairability:
Proper service and repair is important to the safe, reliable operation of all series products. The service providers recommended by vender should be aware of notices listed in this service manual in order to minimize the risk of personal injury when perform service procedures. Furthermore, the possible existed improper repairing method may damage equipment or products. It is recommended that service engineers should have repairing knowledge, experience, as well as appropriate product training per new model before performing the service procedures.

NOTICE:

• To avoid electrical shocks, the products should be connected to an authorized power cord, and turn off the master power switch each time before removing the AC power cord.
• To prevent the product away from water or expose in extremely high humility environment.
• To ensure the continued reliability of this product, use only original manufacturer's specified parts.
• To ensure following safety repairing behavior, put the replaced part on the components side of PWBA, not solder side.
• To ensure using a proper screwdriver, follow the torque and force listed in assembly and disassembly procedures to unscrew screws.
• Using Lead-Free solder to well mounted the parts.
• The fusion point of Lead-Free solder requested in the degree of 220°C.