IMPORTANT SAFETY NOTICE Proper service and repair is important to the safe, reliable operation of all Philips Consumer Electronics Company** Equipment. The service procedures recommended by Philips and described in this service manual are effective methods of performing service operations. Some of these service operations require the use of tools specially designed for the purpose.
FIRE AND SHOCK HAZARD 1. Be sure all components are positioned in such a way as to avoid the possibility of adjacent component shorts. This is especially important on those chassis which are transported to and from the service shop. 2.
LEAKAGE CURRENT COLD CHECK 1. Unplug the ac line cord and connect a jumper between the two prongs of the plug. 2. Turn on the power switch. 3. Measure the resistance value between the jumpered ac plug and all exposed cabinet parts of the receiver, such as screw heads, antennas, and control shafts.
TV SAFETY NOTES SAFETY CHECKS After the original service problem has been corrected, a complete safety check should be made. Be sure to check over the entire set, not just the areas where you have worked. Some previous servicer may have left an unsafe condition, which could be unknowingly passed on to your customer.
The use of a substitute part which does not have the same safety characteristics as the Philips recommended replacement part shown in this service manual may create shock, fire, or other hazards.
PREVENTION OF ELECTROSTATIC DISCHARGE (ESD) Some semiconductor solid state devices can be damaged easily by static electricity. Such components commonly are called Electrostatically Sensitive (ES) Devices, Examples of typical ES devices are integrated circuits and some field-effect transistors and semiconductor "chip" components. The following techniques should be used to help reduce the incidence of component damage caused by electrostatic discharge (ESD).
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PRACTICAL SERVICE PRECAUTIONS IT MAKES SENSE TO AVOID EXPOSURE TO ELECTRICAL SHOCK. While some sources are expected to have a possible dangerous impact, others of quite high potential are of limited current and are sometimes held in less regard. ALWAYS RESPECT VOLTAGES. While some may not be dangerous in themselves, they can cause unexpected reactions –...
Technical Specifications Supply Supply Voltage 90 – 140Vac Power Consumption 90 W max. Stand By consumption : 7 – 8W Supply Frequency : 50 - 60 Hz 5 % Tuning System Reception NTSC-M Sound System BTSC DBX Sound Output 2 x 5 W – 27”/32”/36” FSQ 2 x 5 W + 10W –...
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MON: CVBS (out) + L/R (out) Cinch CVBS (yellow) (1 V) Cinch Audio L (red) (0.2 - 2 V-RMS / 10 k ohm) Audio R (white) (0.2 - 2 V-RMS / 10 k ohm) YUV (in) Cinch Y (0.7Vpp/ 75 ohm) Cinch U (0.7Vpp/ 75 ohm) Cinch V...
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Model to Module Listings MODEL PANEL 27PT31B/121 313917867841 Large Signal Panel 313917883531 Small Signal Panel 313917880521 M-Link Assembly (W/O M-Link) AVJ400A/001 Side Jack Panel 27PT41B/121 313917867851 Large Signal Panel 313917865621 Small Signal Panel AVJ400A/001 Side Jack Panel A10902A/001 M-Link Assembly A10904A/001 PIP Panel 27PT71B/121...
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32PT41B/121 313917868651 Large Signal Panel 313917865621 Small Signal Panel AVJ400A/001 Side Jack Panel A10902A/001 M-Link Assembly A10904A/001 PIP Panel 32PT71B/121 313917867861 Large Signal Panel 313917863191 Small Signal Panel AVJ400A/001 Side Jack Panel A10902A/001 M-Link Assembly A10901A/001 PIP Panel 310420710191 Receiver Assembly IR Board 32PT81S/128 313917888271 Large Signal Panel...
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32PT91S/121 313917865591 Large Signal Panel 313917865601 Small Signal Panel A10901A/001 PIP Panel (2 Tuner) A10902A/001 M-Link Assembly A10904A/001 PIP Panel 313917865661 Front Interface Panel 313917864271 Top Control Assembly 313917867911 Side Jack Panel 310420710191 Receiver Assembly IR Board 312123751431 Double Window PIP Assembly 313917857061 * Double Window PIP Panel 313917863791...
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33LP803/221 313917867861 Large Signal Panel 313917863191 Small Signal Panel AVJ400A/001 Side Jack Panel A10902A/001 M-Link Assembly A10901A/001 PIP Panel (2 Tuner) 310420710191 Receiver Assembly IR Board Model To Remote Transmitter Listing Model Part Ref. Part No. Transmitter Type 27PT91S/125 AC19 3128 147 12101 RC2037/01 Remote Transmitter 32PT91S/121...
Mechanical Disassembly Rear Cover Removal & Replacement Removal of the Rear Cover 1. Remove all screws from the rear cover. 2. Remove the rear cover. Replacement of the Rear Cover Before replacing the Rear Cover, perform the following inspection: Ensure that AC Cord is placed correctly in the guide brackets. Ensure that all cables are placed in their original position.
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1. Remove the LSP-bracket from the bottom tray by sliding the bracket backward and then pull the bracket up and out of the bottom tray. 2. Place the Hooks (A) of the bracket in the first row of fixation holes of the cabinet bottom. In other words reposition the bracket hooks from position (1) to position (2).
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Service position for the Small Signal Board (SSB) There is not a predefined service position for the bottom (B-) side of the SSB. All relevant test points can be accessed in both LSB service positions. If IC's must be replaced: take the complete panel out of the SIMM-connector. 1.
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Access to the Side I/O Panel 1. Remove the two screws. 2. Remove the complete Side I/O-assembly. 3. Release the two clamps then lift the board out of the bracket.
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Access to the Mains Switch/LED Panel 1. Release the two clamps (1) by pulling them upward. 2. While pulling upward on the clamps, slide the complete assembly backward (2). 3. If it is necessary to remove the board, release the two clamps at the sides of the bracket and lift the board out (3). 1.
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Access to the PIP Panel 1. Release the two clamps (1) and remove the PIP CBA from the bracket. Access to the Guide+ Panel 1. Remove the two screws that secure the Guide+ assembly in place. This will release the complete Guide+ assembly. 2.
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Access to the M-Link 1. Release the two clamps at both sides and remove the board from the bracket. Access to the DC-shift/DAF panel 1. Release the clamps (1) and remove the board (2) from the bracket.
Troubleshooting Tips Troubleshooting tips for the deflection and power supply circuitry. The Deflection Circuit: Measure for VBAT (140V) across 2939/2940 (Section - A1 POWER SUPPLY). If the voltage is not present, disconnect jumper 9936 and 9937 (see A1 Power Supply) The complete Line Deflection stage is now disconnected.
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Solving other problems TV switched off or changes channel without any user action Set switches off after “TV SWITCHING OFF” was displayed Auto standby switched the set off because: there was no ident signal for more than 15 minutes there was no remote control signal received or local key pressed for > 2 hours See Service Adjustments for a description of options to enable/disable auto standby.
H8 CHASSIS (A10) ADJUSTMENTS Electrical Adjustments Conditions All electrical adjustments should be performed under the following conditions: Supply voltage: 120V +/- (10%) Warm-up time: 10 minutes The voltages and oscilloscope waveforms are measured in relation to the tuner ground. Test probe: Ri > 10Meg Ohm; Ci < 2.5 pF. VG2 Adjustment Rough alignment Using a pattern generator displaying a circle pattern, adjust the VG2 potentiometer of LOT L5630 to obtain a normal picture.
Focus Adjustment Using a pattern generator displaying a crosshatch pattern, adjust the focus potentiometer of LOT L5431 in such a way that the haze on the vertical lines at 2/3 from the left and right edges of the screen (just) disappears. PIP AGC Adjustment The Automatic Gain Correction adjustment prevents overdriving of the PIP-tuner if the input signal is too strong.
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PIP AFC Adjustment Connect a video generator with a color bar and a frequency of 61.25 MHz to the tuner. Connect a multimeter to the AFC output on pin 15 of IC 7914 – TDA9801 Use potentiometer R3944 to adjust the AFC output to 2.6 Volts. Software alignments (Service Alignment Mode) With the software alignments of the Service Alignment Mode, the geometry, white tone and tuner (IF) can be aligned.
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Tuner (Large Signal Panel and Double Window) AGC Adjustment Set pattern generator with gray scale video signal and connect to antenna input with RF signal amplitude - 10mV and set frequency to 63.25 MHz. Enter SAM (see Software alignments (Service Alignment Mode)). Press Cursor Down button to highlight the TUNER menu item.
Geometry Adjustment The geometry alignments menu contains 13 items for correct picture geometry alignment. In widescreen models, the GEOMETRY SW is available for separate alignments of the superwide (panorama) mode. The geometry alignments are: Initial set-up: Press the PICTURE button on the remote control repeatedly to change the Smart Picture setting to "SPORTS." Enter SAM (see Software alignments (Service Alignment Mode)).
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Geometry Submenu Item Descriptions SERV-BLK: - To turn on/off the blanking of the lower half of the screen (To be used in combination with the vertical slope alignment) VER-SLOPE - To adjust the picture so the proportions are the same at the top and bottom of the screen. (This alignment must be performed first, before all other vertical alignments) VER-AMPL - To align the picture height (other vertical alignments are NOT compensated)
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Option Codes for Single Tuner PIP, and 2 Tuner PIP...
Service Modes & Error Messages The following topics are covered: Test points Service Modes and Dealer Service Tool (DST) Error code buffer and error codes The “blinking LED” procedure Trouble shooting tips Customer Service Mode Test points The H8 chassis is equipped with test points shown on the CBA and the schematic diagrams. Large Signal Panel PCB Test Point Guide...
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Small Signal Panel PCB Test Point Guide...
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CRT Panel PCB Test Point Guide Each test point has a reference number indicating the functional block in which it is located. A1-A2-A3, etc.: Test points for the audio processing circuitry [A6, C6] C1-C2-C3, etc.: Test points for the control circuitry [C8] F1-F2-F3, etc.: Test points for the frame drive and frame output circuitry [A3] I1-I2-I3, etc.: Test points for the Intermediate Frequency Circuitry [A4, C1] K1-K2-K3, etc: Test points for the Guide+ panel...
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Service Default Mode (SDM) Introduction The Service Default Mode (SDM) is a technical aid for the service technician. The Service Default Mode (SDM) establishes fixed, repeatable settings of customer controls, which allow consistent measurements to be made. The SDM also initiates the blinking LED procedure and, if necessary, overrides the 5V protection.
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Service Default Mode (SDM) Screen Special SDM functions Access to normal user menu Pressing the “MENU” button on the remote control switches between the SDM and the normal user menus (with the SDM mode still active in the background) Auto Program Press the Cursor Down button and highlight the "Install"...
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Service Alignment Mode (SAM) Introduction The Service Alignment Mode (SAM) is used to align the set and/or adjust the option settings and to display/clear the error code buffer values. Entering Service Alignment Mode To enter the Service Alignment Mode (SAM), press the following key sequence on the remote control transmitter: 0-6-2-5-9-6-STATUS Do not allow the display to time out between entries while keying the sequence It is also possible to enter the Service Alignment Mode by pressing the “VOLUME +”...
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Explanation notes/references: Operation Hours (Run Timer): This display indicates the accumulated total of operational hours. (Shown in hexadecimal format) Software identification of the main micro controller (A10US1-2.7) A10 is the engineering chassis name for the H8 chassis US1 is 2 letter and 1 digit combination to indicate the software type and the supported languages: US = USA 1 = Main Software language version number...
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upon automatic reset when content has not changed for 50 consecutive hours By leaving SDM or SAM via the power switch, the error buffer will not be reset. Examples: ERROR: 0 0 0 0 0 0 0 : No errors detected ERROR: 6 0 0 0 0 0 0 : Error code 6 is the last and only detected error ERROR: 9 6 0 0 0 0 0 : Error code 6 was first detected and error code 9 is the last detected (newest) error The contents of the error buffer can also be displayed by use of the “blinking LED”...
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Error 4 = +5V protection 5V protection active; set is switched to protection; error code 4 is placed in the error buffer; the LED will blink 4 times (repeatedly). A 5V failure can cause a drop in the 5V-supply output, resulting in an undefined behavior of the set. Therefore, all I 2 C devices connected to the 5V supply are constantly monitored.
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Error 16 = PIP/DW Tuner I 2 C error. The Tuner (TEDE9 – item 1900) on the PIP-panel does not respond to the micro controller. Error 17 = PIP IC – M65669SP I 2 C failure (item 7803) or Double Window IC SAB9081 I 2 C failure. Error18 = I/O expander IC –...
The Blinking LED Procedure The contents of the error buffer can also be made visible through the “blinking LED” procedure. This is especially useful when there is no picture. When the SDM is entered, the LED will blink the number of times, equal to the value of the error code. Upon entry into the SDM, the LED will blink the contents of the error-buffer.
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The Customer Service Mode information screen Upon entry into the Customer Service Mode the following screen will appear. CSM Menu Screen The Customer Service Menu shows the following information: Line 1 : “HRS : nnnnn” and SWID : “A10BBC-X.Y” HRS: Indicates the accumulated total of operational hours.
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Line 6 : “TIMER ON ” Indicates that the on/off timer is running. The following Complaints may be caused by the activation of the sleep timer: The set may turn on from standby or may switch to a different channel without using either the remote control or the local keyboard.
H8 Technical Training INTRODUCTION The H8 TV Chassis is designed for the 2000-2001 model years. It comes in three screen sizes, which are 27, 32, and 36 inch. All Chassis versions have a Side Jack Panel, a Component Input, and Surround Speaker Jacks.
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The Power Supply is a Switching type supply. The Power Supply begins operating as soon as AC power is applied to the set. AC power is applied to the Large Signal Board through Fuse 1900 and applied to the Bridge Rectifier 6915.
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The voltage from jumper 9964 (approximately 8 volts) is used to produce the 3.3 volt standby, 5 volt standby, 5 volt remote control, and switched 8 volt supplies. The voltage is applied to transistor 7965 to produce the 3.3- volt Standby supply. When the set is in the Standby mode, transistor 7944 is turned On, turning 7922 On, providing a extra current drive for the 3.3 volt regulator.
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Power Down and Front Detect Figure 4 The Power-Down and Front Detect circuits signal the Microprocessor in case power is removed from the set. The Microprocessor will store the customer settings before shutting the set down. Diode 6942 produces a negative voltage to turn transistor 7987 On, keeping the Power-Down line High.
SWEEP AND SHUTDOWN CIRCUITS Horizontal and Vertical Drive Figure 5 The 3.3 volts Standby supply provides power to 7301 on Pin 14 for a Horizontal Soft Start. The Standby line from the Microprocessor turns the +8 volt supply On to provide power for the Sync circuits when the set is turned On.
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Horizontal Output and Shutdown Figure 6 Horizontal Drive (LINEDRIVE1) is fed to transistor 7481 and coupled through transformer 5406 to the Horizontal Output transistor 7410. In sets with the Very Flat CRT and larger screen sizes, an East West Drive circuit is present.
Vertical Output Figure 7 Positive and Negative Vertical drive from the Small Signal Board is fed to the Vertical Output IC7501 which drives the Vertical Yoke. The Vertical Pulse on Pin3 drives 7513 to produce the VFB (Vertical Feedback signal) for the Small Signal Board.
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NON PIP Video Signal Flow Figure 8 The first version to be discussed is the Non PIP chassis video path. The Main Tuner, AV1, AV2, and Component Inputs are located on the Large Signal panel. The AV3 input is located on the Side Jack Panel. All of these inputs are fed to the Small Signal Board, SSB, which plugs into the Large Signal panel.
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Standard CRT Drive Figure 9 The CRT drive signal is fed to 7830, which drives the CRT. As mentioned previously, a Test Signal is sent to 7830 and to the CRT. The Waveform on the left shows this Test Signal. When 7830 senses the correct current flow in the CRT, the Test Signal is sent to the SSB via the CUTOFF line.
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PIP (Picture in Picture) Video Flow Figure 10 There are two PIP chassis versions which are the Single Tuner and Two Tuner sets. Video Signal flow for the Single Tuner PIP version is the same as the Two Tuner version, except the Composite Video from Pin 16 of 7301 is routed through the Large Signal Board (LSB) to the PIP module and back to the 1333 Sound Trap in the Two Tuner version.
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PIP Circuit Figure 11 The PIP comes in two versions, Single Tuner with no tuner on the PIP panel and two tuner versions with the second tuner located on the PIP module. Output of the second tuner is fed to the SAW FILTER 1901, and to the Signal Processor 7914.
PIP Switching Figure 12 Control for the PIP panel is performed by 7910 via the I2C buss. SEL_TUNER1 and SEL_TUNER2 control the composite switching to the SSB panel. S1, S2, and S3 control the tuner aux switching IC 7801.PIP...
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Power Supply Figure 13 The PIP panel is powered by +5 volt, +8 volt, and +33 volt supplies from the Large Signal Board (LSB). A 3.3 volt regulator supplies power to the PIP processor, 7803.
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Video Signal Flow with Double Window Figure 14 The XXPT91 versions of the H8 chassis have the DOUBLE WINDOW panels. This allows for both a single PIP window and a split screen. Each Time the PIP On/Off button on the remote is selected, the PIP window goes from a small window to a large window and then to a split screen.
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Double Window Tuner and Video Switching Figure 15 The PIP/Double Window panel allows for both a standard PIP window and a split screen. The PIP/Double Window module has a separate Tuner, SAW filter, and Signal Processor. The output of the Signal Processor, 7301, on Pin 16 is fed to switching IC 7402 which selects between the PIP Tuner and Composite Video from the SSB for feedback to the SSB on Pin 15 or Video for the PIP window on Pin 14.
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Double Window Output Figure 16 The PIP or Double Window YUV signal is fed to the PIP/DW processor, 7801. The I2C buss controls the IC from the Microprocessor on the SSB. The PIP/DW processor outputs YUV for the PIP window or Split Screen to the YUV switch 7803 where it is mixed with the YUV signal from the SSB for the main picture.
Double Window Control and Power Supply Figure 17 The PIP/Double Window module is controlled by the I2C buss through 7403 on the PIP module. Pins 4, 5, 6, and 7 perform Video selection functions. Pin 10 produces a reset signal for the Guide Plus module. Pin 12 controls the +5VS and +8VS supplies.Very...
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Flat CRT Drive Circuit Figure 18 The CRT panel for the Very Flat CRT's has an SVM circuit to sharpen the transitions from dark to light and light to dark. The RGB signals are combined and fed to 7860 which performs impedance matching. The signal is then buffered by 7861.
AUDIO SIGNAL PATH Audio Signal Processing Figure 19 All Audio Processing is performed by 7651, which is located on the SSB. The Sound IF is fed to Pin 50 and to the Sound Demodulator for decoding. The internal Switch selects between AV1, AV2, and AV3. The Audio is digitally processed inside the IC to separate the Second Audio Program and process volume levels to maintain a constant audio level if the user selects the AVL feature.
Audio Amplifier Figure 20 Audio from the SSB is fed to the Audio Amplifier on the LSB. Left Channel Audio is fed to Pin 2 of 7702 while Right Channel Audio is fed to Pin 5. Audio is output to the speakers on Pins 12 and 7. Left and Right outputs are also fed to the Surround Sound Speaker Jack.
Headphone Amplifier Figure 21 Headphone audio from the SSB is fed to the Headphone Amplifier, 7703-A, located on the LSB. The Audio is then output to the Side Jack panel. This circuit is powered by the +5 volt supply.
Side Jack Panel Figure 22 The Side Jack panel is the AV3 input in the Customer Menu. It has a Composite Video Input, SVHS Input, and a Stereo Audio input. It also has a headphone output. If an SVHS connector is plugged into the Side Jack panel, the Composite Video input is muted.
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Microprocessor Figure 23 The Microprocessor, 7064, is located on the SSB. User control of the Microprocessor is accomplished via the Keyboard or Remote. In case of Overcurrent or a failure in the Horizontal sweep circuit, The PROT-UP line will go High turning transistor 7276 On, placing a Low on Pin 5 of the Keyboard line. The Microprocessor will then shut the set Off.
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Customer Control Interface Figure 24 The Keyboard line is a voltage level controlled input. With no buttons pressed, this line should read approximately 3.38 volts when the set is On. It will be approximately 0.2 volts higher when the set is in Standby. In the XXPT31 versions, the Keyboard Switches are located on the LSB.
SERVICE MODES All of the adjustments in the set are performed via the On-Screen Service mode. There are three different Service Modes. The SDM (Service Default Mode) allows Error Codes to be read through an On-Screen menu or from a blinking Power light. It also pre-sets certain conditions and disables certain functions. The next Service mode is the SAM (Service Adjustment Mode).
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Service Alignment Mode (SAM) Figure 25 The Service Alignment Mode is used to read Error Codes, Reset Error Codes, Set Option Codes, and perform Service Alignments. Pressing 0-6-2-5-9-6-Status on the remote control transmitter enters the SAM. To save the Error Codes, remove AC power to the set without turning it Off. When power is reapplied and the set is turned On, the SAM will still be active.
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Customer Service Mode (CSM) The Customer Service Mode allows the Customer to read the Error codes upon instruction form the Technician. Pressing the Mute button on the Remote Control and any key on the set Keyboard at the same time can enter the Customer Service Mode.