LCD TELEVISION LC-42T17 LC-47T17 CONTENTS Safety precautions………………………………………………………………………..… Alignment instructions …………………………….…….…………………………….… Working principle analysis of the unit……………………………….………….…………. Block diagram…………………………………..……………………….………… IC block diagram………………………………………………………………………..…… Wiring diagram ……………………………………………………………………………..… Troubleshooting………………………………………………………………..…… Schematic diagram …………………………………………………………………….….. APPENDIX: Main assembly list 1 3 7 9 10 22 23 31 1 Safety precautions 1. Instructions Be sure to switch off the power supply before replacing or welding any components or inserting/plugging in connection wire Anti static measures to be taken (throughout the entire production process!): a) Do not touch here and there by hand at will; b) Be sure to use anti static electric iron; c) It’s a must for the welder to wear anti static gloves. Please refer to the detailed list before replacing components that have special safety requirements. Do not change the specs and type at will. 2. Points for attention in servicing of LCD 2.1 Screens are different from one model to another and therefore not interchangeable. Be sure to use the screen of the original model for replacement. 2.2 The operation voltage of LCD screen is 700-825V. Be sure to take proper measures in protecting yourself and the machine when testing the system in the course of normal operation or right after the power is switched off. Please do not touch the circuit or the metal part of the module that is in operation mode. Relevant operation is possible only one minute after the power is switched off. 2.3 Do not use any adapter that is not identical with the TV set. Otherwise it will cause fire or damage to the set. 2.4 Never operate the set or do any installation work in bad environment such as wet bathroom, laundry, kitchen, or nearby fire source, heating equipment and devices or exposure to sunlight etc. Otherwise bad effect will result. 2.5 If any foreign substance such as water, liquid, metal slices or other matters happens to fall into the module, be sure to cut the power off immediately and do not move anything on the module lest it should cause fire or electric shock due to contact with the high voltage or short circuit. 2.6 Should there be smoke, abnormal smell or sound from the module, please shut the power off at once. Likewise, if the screen is not working after the power is on or in the course of operation, the power must be cut off immediately and no more operation is allowed under the same condition. 2.7 Do not pull out or plug in the connection wire when the module is in operation or just after the power is off because in this case relatively high voltage still remains in the capacitor of the driving circuit. Please wait at least one minute before the pulling out or plugging in the connection wire. 2.8 When operating or installing LCD please don’t subject the LCD components to bending, twisting or extrusion, collision lest mishap should result. 2.9 As most of the circuitry in LCD TV set is composed of CMOS integrated circuits, it’s necessary to pay attention to anti statics. Before servicing LCD TV make sure to take anti static measure and ensure full grounding for all the parts that have to be grounded. 2.10 There are lots of connection wires between parts behind the LCD screen. When servicing or moving the set please take care not to touch or scratch them. Once they are damaged the screen Attention: This service manual is only for service personnel to take reference with. Before servicing please read the following points carefully. 2 would be unable to work and no way to get it repaired. 2.11 Special care must be taken in transporting or handling it. Exquisite shock vibration may lead to breakage of screen glass or damage to driving circuit. Therefore it must be packed in a strong case before the transportation or handling. 2.12 For the storage make sure to put it in a place where the environment can be controlled so as to prevent the temperature and humidity from exceeding the limits as specified in the manual. For prolonged storage, it is necessary to house it in an anti-moisture bag and put them altogether in one place. The ambient conditions are tabulated as follows: Temperature Scope for operation 0 ~ +50 oC Scope for storage -20 ~ +60 oC Humidity Scope for operation 20% ~ 85% Scope for storage 10% ~ 90% 2.13 Display of a fixed picture for a long time may result in appearance of picture residue on the screen, as commonly called “ghost shadow”. The extent of the residual picture varies with the maker of LCD screen. This phenomenon doesn’t represent failure. This “ghost shadow” may remain in the picture for a period of time (several minutes). But when operating it please avoid displaying still picture in high brightness for a long time. 3. Points for attention during installation 3.1 The front panel of LCD screen is of glass. When installing it please make sure to put it in place. 3.2 For service or installation it’s necessary to use specified screw lest it should damage the screen. 3.3 Be sure to take anti dust measures. Any foreign substance that happens to fall down between the screen and the glass will affect the receiving and viewing effect 3.4 When dismantling or mounting the protective partition plate that is used for anti vibration and insulation please take care to keep it in intactness so as to avoid hidden trouble. 3.5 Be sure to protect the cabinet from damage or scratch during service, dismantling or mounting. 3 Alignment instructions (LC-37T25& LC-42T17&LC-47T17) 1. Test equipment Digital multimeter, signal generator (54200) VG849 (HDMI signal generator) CA210 (White balancer) 2. The alignment flow chart (see below Fig.1) Fig.1 Flow process of alignment 3. Alignment instructions 3.1 the main board adjustment a. Connect the X602 of main board to the infrared receive board, the supply power plug to X1, then Check accessories and then packing Write N105, N403, N607, N70, N606 To produce main board, TV board and other board Check the MAIN board Check the buttons board and IR receive board Combined test for general assembly Input AV1/S/AV2 signal source, check if the various terminal functions (system identify and analog control etc.) and the picture and sound of AV-out is normal. Check the TV board Input YpbPr/YcbCr 1/2 signal source; check if the picture and sound analog control is normal in the COMPONENT state. The AV-out output sound is originally signal Input HDMI and DVI signal source, check if the HDCP KEY is normal. The AV-out output sound is originally signal Input VGA signal source, check is the display is normal in PC state and various function (analog control) H-V center etc. The AV-out output sound is originally signal Aging Input the center signal source, check if various functions of TV (search channel, system identify and analog control etc.), earphone output, speaker output and the picture and sound of AV-out is normal ADC correction and white balance adjustment 4 the indicator of the infrared receive board is red light. b. Press the POWER button; the indicator change to blue light, the LED1 of main board is flicker of slow. c. Write program to N102 d. Check if various channels are normal. 3.2 The TV board adjustment a. Connect the high frequency board to main board, and connect the X501 and X502 to the supply power. b. Press the POWER button, the indicator change to blue light. c. Check if the picture and sound of TV/AV1/AV2/S/YPBPR1/TPBPR2 and sound of HDMI/VGA channels are normal. Check the STEREO and SAP. Check the picture and sound of the TV/AV1/S/AV2. 3.3 the unit adjustment After install the unit, check it is normal working. 3.4 Aging a. Select the TV channel, the screen is noise wave of no signal TV b. Aging an hour. 3.5 ADC correction and white balance adjustment (use white balancer CA210 and signal generator VG849) Enter the factory menu method: press “1”→ “9” → “7” → “9” button in the window menu state. Note: warm color temperature coordinate (285, 294); warm color temperature coordinate (284, 299). LC-42T17, LC-47T17 and LC37T25/T7 cool color temperature coordinate (270, 283). 3.5.1 HDMI channel a. Input 8 level gray signal 720p/60Hz. b. Brightness to 50, contrast to 50. c. Color temperature to warm. d. Enter color temperature setup menu. e. Adjust RED GAIN, GREEN GAIN, BLUE GAIN, until the fifth level color coordinate (270, 283). 3.5.2 D-SUB channel a. Input the 16 level gray signal 1027 x 768 @ 60(TIMING: 889, PATTERN: 921) b. Brightness to 50, contrast to 50. c. Enter the ADC auto correction d. Color temperature to warm. e. Enter the color temperature setup menu. f. Input the 8 level gray signal 1027 x 768 @ 60(TIMING: 889, PATTERN: 920) g. Adjust the RED OFFSET, GREEN OFFSET, BLUE OFFSET, until the third level color coordinate (284, 299). h. Adjust the RED GAIN, GREEN GAIN, BLUE GAIN, until the seventh level color coordinate (284, 299). i. Repeat the g and h step, until the third and the seventh level color coordinate (284, 299). j. Color temperature to cool. k. Enter the color temperature setup menu. l. Adjust the RED OFFSET, GREEN OFFSET, BLUE OFFSET, until the third level color coordinate (270, 283). m. Adjust the RED GAIN, GREEN GAIN, BLUE GAIN, until the seventh level color coordinate (270, 5 283). n. Repeat the L and M step, until the third and the seventh level color coordinate (270, 283). 3.5.3 high definition channel a. Input the 720P SMPTE COLOR BAR signal (TIMING: 976, PATTERN: 984). b. Brightness to 50, contrast to 50. c. Enter the ADC auto correction. d. Color temperature to warm. e. Enter the color temperature setup menu. f. Input the 8 level gray signal 720b/60Hz(TIMING: 976, PATTERN: 920). g. Adjust the RED OFFSET, GREEN OFFSET, BLUE OFFSET, until the fourth level color coordinate (284, 299). h. Adjust the RED GAIN, GREEN GAIN, BLUE GAIN, until the seventh level color coordinate (284, 299). i. Repeat the g and h step, until the fourth and the seventh level color coordinate (284, 299). j. Color temperature to cool. k. Enter the color temperature setup menu. l. Adjust the RED OFFSET, GREEN OFFSET, BLUE OFFSET, until the fourth level color coordinate (270, 283). m. Adjust the RED GAIN, GREEN GAIN, BLUE GAIN, until the seventh level color coordinate (270, 283). n. Repeat the l and m step, until the fourth and the seventh level color coordinate (270, 283). o. Holding the pattern signal, change the timing signal, repeat the G to the M step for 480i, 480p, and 1080i signal. 3.5.4 the VIDEO channel a. Input the eight level gray signal of PAL b. Brightness to 50, contrast to 50. c. Enter the factory menu. d. Color temperature to warm. e. Enter the color temperature setup menu. f. Adjust the RED OFFSET, GREEN OFFSET, BLUE OFFSET, until the fourth level color coordinate (284, 299). g. Adjust the RED GAIN, GREEN GAIN, BLUE GAIN, until the seventh level color coordinate (284, 299). h. Repeat the f and g step, until the fourth and the seventh level color coordinate (284, 299). i. Color temperature to cool. j. Adjust the RED OFFSET, GREEN OFFSET, BLUE OFFSET, until the fourth level color coordinate (270, 283). k. Adjust the RED GAIN, GREEN GAIN, BLUE GAIN, until the seventh level color coordinate (270, 283). l. Repeat the j and k step, until the fourth and the seventh level color coordinate (270, 283). 3.5.5 the RF channel a. Input the center signal source, set to D-8 channel b. Brightness to 50, contrast to 50. c. Enter the factory menu. d. Color temperature to warm. 6 e. Enter the color temperature setup menu. f. Adjust the RED OFFSET, GREEN OFFSET, BLUE OFFSET, until the third level color coordinate (284, 299). g. Adjust the RED GAIN, GREEN GAIN, BLUE GAIN, until the seventh level color coordinate (284, 299). h. Repeat the f and g step, until the third and the seventh level color coordinate (284, 299). i. Color temperature to cool. j. Adjust the RED OFFSET, GREEN OFFSET, BLUE OFFSET, until the third level color coordinate (270, 283). k. Adjust the RED GAIN, GREEN GAIN, BLUE GAIN, until the seventh level color coordinate (270, 283). l. Repeat the j and k step, until the third and the seventh level color coordinate (270, 283). 4 Performance check 4.1 TV terminal Input the center signal source to RF terminal, enter searching menu → auto search, check if the leak channel, half-auto search channel, fine tune, earphone and speaker are normal. Check the AV OUT. 4.2 AV1/S/AV2 input terminals Input AV1/S/AV2 signal source, check the picture and sound. 4.3 VGA terminal Input the VGA signal (K7253 signal generator), separate input VGA format signal of table 1, check the picture and sound Table1 PC display format signal No. Resolution H-frequency(kHz) V-frequency(Hz) pixel clock pulse frequency(MHz) remark 1 720 x 400 31.47 70.08 25.17 DOS 2 640 x 480 31.50 60.00 25.18 DOS 3 640 x 480 37.90 72.00 31.50 Mac.(SOG) 4 640 x 480 37.50 75.00 31.50 VESA 5 640 x 480 43.30 85.00 36.00 VESA 6 800 x 600 35.16 56.25 36.00 VESA 7 800 x 600 37.90 60.00 40.00 VESA 8 800 x 600 46.90 75.00 49.50 VESA 9 800 x 600 48.08 72.19 50.00 VESA 10 832 x 624 49.00 74.00 57.27 Mac.(H+V) 11 1024 x 768 48.40 60.00 65.00 VESA 12 1024 x 768 56.50 70.00 75.00 VESA 13 1024 x 768 60.00 75.00 78.75 VESA 14 1280 x 1024 64.00 60 108.00 SXGA 15 1280 x 1024 80.00 75 135.00 SXGA 16 1600 x 1200 75.00 60 162.00 UXGA 4.4 YPbPr terminal Input the YPbPr signal source (K7253 signal generator), separate input format signal in table of 7 table 2, check the picture and sound. Table 2 Component format signal No. H-frequency(kHz) V-frequency(Hz) signal 1 15.735 60 SDTV 480i 2 15.625 50 SDTV 576i 3 31.47 60 SDTV 483p 4 45.00 60 HDTV 720p 5 33.75 60 HDTV 1080i 6 28.13 50 HDTV 1080i 7 67.50 60 HDTV 1080p 8 56.25 50 HDTV 1080p 4.5 HDMI terminal Input the DHMI signal source (VG849 signal generator), separate input format signal in table of table 3, check the picture and sound. Table 3 HDMI format signal No. H-frequency(kHz) V-frequency(Hz) signal 1 15.735 60 SDTV 480i 2 15.625 50 SDTV 576i 3 31.47 60 SDTV 483p 4 45.00 60 HDTV 720p 5 33.75 60 HDTV 1080i 6 28.13 50 HDTV 1080i HDMI format signal of audio channel 2 sampling rate support 32Kbit/s 44.1Kbit/s 48Kbit/s bit wide support 16bit,20bit,24bit Working principle analysis of the unit The unit has two MCU, the main MCU is PW218 (N601): it is used to control all the chips’ working status on the main board (including image processing, channel switch, sound processing, image display etc.), sub CPU, OSD, searching channels, image effect adjustment, buttons control, infrared remote control etc.; the sub CPU is ATMEGA8L (N606): it is used to control power supply, including standby and turning on the unit by using remote control etc.. The two MCU correlates with each other through pin 14 INT (interruption) of ATMEGA8L, pin 28 and 29 SDA, SCL. The unit has one integrative tuner (including HF and IF amp. circuits). The signal received by antenna is sent to tuner, under the control of MCU PW218 (N601) SDA and SCL, proper channel selection and right system switching will be done by the tuner, then video signal and audio signal will be output by the tuner through decoding and by high and intermediate amplification. Video signal of the tuner will then be sent to Decoder PW2300 (N201). Audio signal of the tuner will then be sent to AV switch box M52797 (N400), the audio signal of AV1, AV2 and HD2 of the main board will also be sent to M52797 (N400) at the same time. The selected audio signal after switching will be sent to R2S15900 (N301), and then switching selection will be done towards the above audio signal together with the audio signal of VGA, HDMI and HD1. The two chips are controlled by 8 PW218 (N601), after the above process the finally selected way will be set to X300 earphone socket after under the control of volume, treble and bass which is finished by R2S15900 (N301), the earphone socket has the switching function, when earphone is plugged, sound will be sent to earphone amplifier NJW1109 (N302), then sent back to earphone socket after power amplification. If earphone is unplugged, sound will be sent to sound amplifier TPA3008 to do amplification and then sent to speaker. Image parts: Video signal of the tuner will be sent to AV switch box M52797 (N400), video signal of AV1 and AV2 will also be sent to M52797 (N400) at the same time, two groups of video output will be obtained after switching, one group of video output together with its audio output will be sent to AV_OUT terminal to treat as AV OUT. The other group of video output together with other video signals such as S-VIDEO, YpbPr1, YpbPr2 and VGA will be sent to PW2300 to do video decoding or AD transformation, then output 24bit digital RGB signal and some corresponding synchronous signals. Items such as 3D comb filter, channel switching, 5 lines Y/C separation and color decoding etc. are primarily done by PW2300. 24bit digital RGB signal and some corresponding synchronous signals outputted by PW2300 will then be sent to PW218 (N601). HDMI signal will also be sent to AD9398 (N101) to de decoding and output 24bit digital RGB signal as well as some corresponding synchronous signal, which will be sent to PW218 (N601). PW218 is a new generation chip of Pixelworks, which has ability to deal with images, 24bit digital RGB signal and some corresponding synchronous signals outputted by AD9398 and PW2300 will be sent to this chip to deal with images. The chip has functions such as converting from interleaved into line-by-line and image enhancement etc.. PW218 has SCALER function which can do format conversion towards different input formats so as to meet the format needs of the screen and finally output 24bit RGB signal. The interface standard of PDP screen is generally LVDS (low voltage differential signal), so the digital RGB signal outputted from PW218 is needed to send to converting interface chip N6 DS90C387 of LVDS to obtain LVDS signal, then it will be sent to the screen. PW218 is also the main CPU, its programs are stored in periphery device flash N701, and software upgrade through RS-232 interface is virtually upgrading the stored programs through PW218 towards N701. Chief functions: High definition 1080P LCD 16:9 wide screen Support several kinds of HDTV wide voltage range, low standby power consumption (less than 1W) One group of D-SUB, S-VSH (Y/C), RS232, AVOUT, HEADPHONE, HDMI, two groups of YPbPr/YCbCr, AV. Block diagram N400 M52797SP Audio and video switch R2S15900 PW218 Flash DDR 256M SDRAM V port G port HDMI AD9880 Or AD9398 PC YPbPr2 Tuner AV1 YPbPr1 AV2 PW2300 memory NJW1109 SRS processor M62494 TPA3008D2 LA72700V STERO/SAP decoder RF Video RF Audio Earphone socket of with switch PC Audio HDMI Audio YPbPr2 YPbPr1 RS232 AV Audio Out I2C1 S PCM1742 I2S D/A DS90C387 LCD panel MEGAL8 EEPROM 24LC32 I2C2 IR KEY AV MAX3232C KEY EEPROM PW2300 10 IC block diagram 1. AD9880 and AD9398 AD9880 have HDMI digital and analog terminal of working frequency 165Hz, it support 1080P (non-interlaced scanning) and UXGA (1600 x 1200/60Hz) video format, also it support eight audio channel of 192KHz. AD9398 without analog terminal. Internal Block Diagram 11 PIN configuration AD9880 (AD9398) PINS FUNCTIONS Pin Name Function Pin Name Function 2-9 GGE(0-7) Converter output 44 RXC+ DVI input 12-19 GBE(0-7) Converter output 49 DDC_CLK HDCP Slave Serial Port Data Clock 92-99 GRE(0-7) Converter output 50 DDC_DATA HDCP Slave Serial Port Data I/O 20, 21 MCLK Control clock output 51 MCL HDCP Master Serial Port Data Clock 22 I2S_SCK Audio serial clock output 52 MDA HDCP Master Serial Port Data I/O 23 I2S_WS Bus clock data output 82 SCL-1 Serial Port Data Clock 12 27 I2S_SD Bus audio data output 83 SDA_1 Serial Port Data I/O 34 RX0- DVI input 84 G_FIEL0 Odd/Even Field Output 35 RX0+ DVI input 85 G_VS VSYNC Output Clock 37 RX1- DVI input 86 G_VHS Sync on Green Slicer Output 38 RX1+ DVI input 87 G_HS HSYNC Output Clock 40 RX2- DVI input 88 G_DE Data Enable 41 RX2+ DVI input 89 G_CLK Data Output Clock 43 RXC- DVI input 2. PW2300 PW2300 is front processing signal of integration highly performance, multi-system, 3D video decoder and three highly velocity AD converter chip. It supports HDTV, NTSC, PAL and SECAM. Its analog port support 1080P(150MHz). Internal Block Diagram PW2300 PINS FUNCTION Pin Name Function Pin Name Function A4 XIN Resonator input P1 R_2 AV2 red input A5 XOUT Resonator input P2 B_2 AV2 greed input B2 SDA I2C bus data P3 SOG_2 AV2 greed sync input 13 B3 SCL I2Cbus clock P4 G_2 AV2 blue input K2 VGA-R1 VGA(red) R1 CVBS_1 TV composite video signal input K1 VGA-G1 VGA(greed) R2 Y_1 S-VHS brightness signal input L1 VGA-SOG1 VGA(greed sync signal) R3 CVBS_SOG1 TV composite video signal greed sync input M1 VGA-B1 VGA(blue) R4 C_1 S-VHS chrominance signal input T1 VGA_H VGA(H-sync signal) B9 GVBI Vertical blanking blank T3 VGA_V VGA(V-sync signal) E16 G_VS V-SYNC output N1 R_1 AV1 red input F14 G_HS H-SYNC output N1 G_1 AV1 greed input F15 G_AHS H-SYNC of non-processing N3 SOG_1 AV1 greed sync input G15 G_DLK Clock output N4 B_1 AV1 blue input GBE(0-7) blue even pixel data output GBO(2-9) Blue odd pixel data output GGE(0-7) greed even pixel data output GGO(2-9) greed odd pixel data output GRE(0-7) red even pixel data output GRO(2-9) red odd pixel data output 3. PW218 PWE218 is highly quality SOC picture processing chip, it contain Scaling and Deinterlacing functions. Internal Block Diagram 14 4. TPA3008 TPA3008 is double channel 10W stereo D class audio amplifier. Internal Block Diagram PINS FUNCTION Pin Name Function Pin Name Function 1 SHUTDOWN Shut down control signal 17 LOUTN Negative audio output for left channel 3 RINP Positive audio input for right channel 20 LOUTP Positive audio output for left channel 4 V2P5 2.5V Reference for analog cells. 27 ROSC I/O current setting resistor for ramp generator. 5 LINP Positive audio input for left channel 41 ROUTP Positive audio output for right channel 11 FAULT Volume control 44 ROUTN Negative audio output for right channel 5. DS90C387 The DS90C387/DS90CF388 transmitter/receiver pair is designed to support dual pixel data transmission between Host and Flat Panel Display up to QXGA resolutions. The transmitter converts 48 bits (Dual Pixel 24-bit color) of CMOS/TTL data into 8 LVDS (Low Voltage Differential Signalling) data streams. Control signals (VSYNC, HSYNC, DE and two user-defined signals) are sent during blanking intervals. At a maximum dual pixel rate of 112MHz, LVDS data line speed is 672Mbps, providing a total throughput of 5.38Gbps (672 Megabytes per second). Two other modes are also supported. 24-bit color data (single pixel) can be clocked into the transmitter at a maximum rate of 170MHz. In this mode, the transmitter provides single-to-dual pixel conversion, and the output LVDS clock rate is 85MHz maximum. The third mode provides inter-operability with 15 FPD-Link devices. Internal Block Diagram Pin Description No. Pin name Description No. Pin name Description 11 CLKIN Clock input 3-10 TTL Red data 54 HSYNC Horizontal sync 93-100, 1, 2 TTL Greed data 55 YSYNC Vertical sync 85-92 TTL Blue data 16 Pin Diagram 6. M62494 (SRS 3D Stereo + SRS 3D Mono processor) M62494 has SRS 3D STEREO and SRS 3D MONO. There are three modes, those are SRS 3D stereo SRS 3D mono and bypass. Each mode can be set by terminals. Pin Description Pin Name Description Pin Name Description 1 Rin1 Right channel of audio input 9 VCC Power 2 Lin1 Left channel of audio input 10 MUTE Mute 5 Rout Right channel of audio output 11 SRS STEREO ON OFF SRS stereo switch 8 Lout Left channel of audio output 12 SRS MONO ON OFF SRS MONO switch 17 Internal Block Diagram 18 7. L72700 Internal Block Diagram Pin description Pin Name Description Pin Name Description 5 PISIF IF of Sound input 25 R OUT Right channel of audio output 11 SDA I2C bus 26 LOUT Left channel of audio output 12 SCL I2C clock 31 VCC 9V supply power 19 8. R2SI5900SP Internal Block Diagram 20 PIN description 2, 27 right/left channel of audio 3, 26 HDMI(right/left channel of audio) 4, 25 VGA(right/left channel of audio) 5, 24 YpbPr1(right/left channel of audio) 11, 19 output the power amplifier(right/left channel of audio) 9. M52797D Internal Block Diagram 21 Pin description Pin Name Description Pin Name Description 3 HD2_L Audio input 5 HD2_R Audio input 6 AV1_L Audio input 8 AV1_R Audio input 9 AV2_L Audio input 11 AV2_R Audio input 27 TV_L Audio input 25 TV_R Audio input 24 Left audio channel output 22 Right audio channel output 10.CM2006 Internal Block Diagram Pin description Pin Name Description Pin Name Description 1 VCC 3.3V 11 DDC_IN2 DDC _input2 3, 4, 5 VIDEO_1_2_3 Video input 12 DDC_OUT2 DDC output 6 GND GND 13 SYNC_IN1 Sync input1 7 Vcc-DDC 5V DDC 14 SYNC_OUT1 Sync output1 8 BYP Bypass capacitance 15 SYNC_IN2 sync intput2 9 DDC_OUT1 DDC output 16 SYNC_OUT2 Sync output2 10 DDC_IN1 DDC _output1 22 Wiring diagram 782-LYT25-0100 12 782-LYT25-5500 \ SUPPLY POWER X3（12） X4 X6 X5 X603 X500 X604 X602 X603 X608 TUNER X601 X101 X401 X402 X8 X7 XA01 CN2 CN3 CN4 CN5 CN1 RS-232C HDMI VGA VGA AUDIO IN S-VIDEO AC220 SPEAKER HEADPHONE KEYS BOARD REMOTE RECEIVER X602 X6 X605 X606 X601 X300 X700 X502 X501 LCD PANEL X604 CNF1 J1 CN2 CN1 YPBPR YPBPR AUDION IN AV IN AV OUT 23 Trouble shooting 1. Fault clearance Before servicing please check to find the possible causes of the troubles according to the table below. 1.1 Antenna (signal): Picture is out of focus or jumping � Bad status in signal receiving � Poor signal � Check if there are failures with the electrical connector or the antenna. � Check if the antenna is properly connected. Fringe in picture � Check if the antenna is correctly oriented. � Maybe there is electric wave reflected from hilltop or building. Picture is interfered by stripe shaped bright spots � Possibly due to interference from automobile, train, high voltage transmission line, neon lamp etc. � Maybe there is interference between antenna and power supply line. Please try to separate them in a longer distance. � Maybe the shielded-layer of signal wire is not connected properly to the connector. There appear streaks or light color on the screen � Check if interfered by other equipment and if interfered possibly by the equipment like transmitting antenna, non-professional radio station and cellular phone. 1.2 TV set: Symptoms Possible cause Unable to switch the power on � Check to see if the power plug has been inserted properly into the socket. No picture and sound � Check to see if the power supply of liquid crystal TV has been switched on. (As can be indicated by the red LED at the front of the TV set) � See if it’s receiving the signal that is transmitted from other source than the station � Check if it’s connected to the wrong terminal or if the input mode is correct. � Check if the signal cable connection between video frequency source and the liquid crystal TV set is correct. Deterioration of color phase or color tone � Check if all the picture setups have been corrected. Screen position or size is not proper � Check is the screen position and size is correctly set up. Picture is twisted and deformed � Check to see if the picture-frame ratio is properly set up. Picture color changed or colorless � Check the “Component” or “RGB” settings of the liquid crystal TV set and make proper adjustment according to the 24 signal types. Picture too bright and there is distortion in the brightest area � Check if the contrast setting is too high. � Possibly the output quality of DVD broadcaster is set too high. � It maybe also due to improper terminal connection of the video frequency signal in a certain position of the system. Picture is whitish or too bright in the darkest area of the picture � Check if the setting for the brightness is too high � Possibly the brightness grade of DVD player (broadcaster) is set too high. No picture or signal produced from the displayer if “XXX in search” appears. � Check if the cable is disconnected. � Check if it’s connected to the proper terminal or if the input mode is correct. There appears an indication - “outside the receivable scope) � Check if the TV set can receive input signal. The signal is not correctly identified and VGA format is beyond the specified scope. Remote control cannot work properly � Check if the batteries are installed in the reverse order. � Check if the battery is effective. � Check the distance or angle from the monitor. � Check if there is any obstruct between the remote control and the TV set. � Check if the remote control signal- receiving window is exposed to strong fluorescence. No picture and sound, but only hash. � Check if the antenna cable is correctly connected, or if it has received the video signal correctly. Blur picture � Check if the antenna cable is correctly connected. � Of if it has received the right video signal. No sound � Check if the “mute” audio frequency setting is selected. � Check if the sound volume is set to minimum. � Make sure the earphone is not connected. � Check if the cable connection is loose. When playing VHS picture search tape, there are lines at the top or bottom of the picture. � When being played or in pause VHS picture search tape sometimes can’t provide stable picture, which may lead to incorrect display of the liquid crystal TV, In this case please press “auto” key on the remote control so as to enable the liquid crystal TV set to recheck the signal and then to display correct picture signal 25 2. Identification criteria for the bright spot and dark spot of the LCD screen Quantity allowed Distance between two spots Category Criteria 15" 20" 22" 30" 40" 15" 20" 22" 30" 40" One single spot ≤5 ≤2 ≤5 ≤2 ≤3 Two neighboring spots ≤2 ≤1 ≤2 ≤1 ≤1 Bright spot Total No. ≤5 ≤2 ≤5 ≤2 ≤3 ≥15mm One single spot ≤6 ≤7 ≤5 ≤4 ≤10 Two neighboring spots ≤2 ≤2 ≤2 ≤1 ≤5 Dark spots Total No. ≤6 ≤7 ≤5 ≤4 ≤10 ≥15mm ≥10mm ≥5mm Total defected point ≤8 ≤7 ≤5 ≤4 / Notes: 1. Definition of defected point (bright spot, dark spot): It is identified as a defected point if its area exceeds 1/2 of a single picture element (R, G, B). 2. Definition of bright spot: It is identified as a bright spot if it is bright in the state of dark field and its bright size remains unchanged 3. Definition of dark spot: It is identified as a dark spot if it is dark in the state of white field and its dark size remains unchanged 4. Definition of two neighboring points: Defects of a group of picture elements (RB, RG, GB). 26 3. Troubleshooting guide 3.1 No raster, no picture and no sound Note: Power supply for PDP is provided with over current and over voltage protection functions. If there is over current or over voltage, this protection will function and no output. Check 5V-STBY Cut off between the power board and signal processing, check the 5V-STB Cut off the the power board and video board to main board, check it Power board problem Check the supply power D3.3V Short circuit the pin 1 (STANDBY) of X604 to 5V, then check the supply power. U24 abnormal Pull out P2 check power Check N501 and N601 Short circuit in a power line Power board problem Abnormal Abnormal Normal Abnormal Normal Check if the indicator is light Yes No Normal Check the supply power of N606 and crystal. Normal Abnormal Check the power of N201, N601, N204 and N701, crystal and bus. 27 2.With sound but no picture: With sound but no picture Display LOGO? Check if no image for all other channels Check if the white balance of the factory menu is normal? Check program Check if the X3, X4 is signal wave? Unfix X3 and X4, turn on the unit display the white screen Check input signal of N601 and power supply Check the supply power (+120) of backlight board N601 damaged Check N201 and the circuit of output part Reset the EEPROM Yes No Yes No Normal Abnormal Normal Abnormal Normal Abnormal Normal Abnormal Yes No The supply power board damaged Check the N201 and peripheral circuit 28 3.With picture but no sound. 4. AV no picture With picture but no sound Sound box damaged Sound power amp. or other peripheral circuit have problem. Check power supply, if SHUTDOWN pin control is normal and if output short circuited or other problems that cause protection to work. Check if input signal in pin 2 of sound power amplification Measure if the sound input of the present channel corresponding to N400 is normal R2S15900 or other peripheral circuit have problem Check different levels of circuit following input audio signal channel No Yes Check if pin 7(AV1) and pin10 (AV2) has signal input Check if the pin1 of X4 has signal output There is problem from Av socket to N102 channel Check the N201 and peripheral circuit N400 or other peripheral circuit have problem PW2300 or other peripheral circuit have problem PW218 or other peripheral circuit have problem Yes No No Yes no Yes If there is output from X700 of sound power amplification board No 29 5. High frequency board overhaul flow 5.1 with picture but no sound Check if other channel is normal Check the circuit of the all levels sound channel Check if the sound channel of N400 is normal Check if the earphone is normal Check the connection cable No Yes R2S15900 and peripheral circuit and earphone socket have problem Normal Yes No No Check if the connection cable and power cable is normal The speaker has problem Yes Yes No Check the audio power amplifier and peripheral. 30 5.2 A certain channel without picture of TV/AV YPBPR Check if the VGA and HDMI has same problem Check the connection cable and signal source is normal Check if the supply power (5v, 9v and 12v) is normal Check the main board Check if the X600 socket is normal Check the YPBPR input circuit No Yes Normal YPBPR channel AV/TV/S channel Check if the X600 socket is normal No Check the supply power Check the main board No No Yes Yes Check the all levels circuit of S terminal channel S terminal channel AV/TV channel Check if the input pin of N400 has signal No Check the M52797 and peripheral circuit Yes Confidential Confidential Confidential Confidential Confidential Confidential Confidential Confidential Confidential Confidential Confidential Confidential Confidential Confidential Confidential Confidential Confidential Confidential APPENDIX: Main assembly list the unit No. part NO. Description 203-L42T170-10 100-L42T170-10 SLC-4217 301-LL37T7-02 RC-L02 remote control 535-L42T17-00 hanging assemble 615-10626-00 stand ASS'Y (DZ-1642S） 615-20548-00 SPEAK ASS'Y 667-L37T7-01 MAIN PCB ASS'Y 667-L42K17-20 POWER PCB ASS'Y (42"CMO) 667-L42T17-05 KEY BOARD ASS'Y 667-L42T17-09 IR RECEIVE ASS'Y 667-L47T17-55 high frequency BOARD ASS'Y KEY1 HDCP SL37T70-01B10 software 37T7mega8 SL37T70-01C10 software 37T7HDMIEDID SL42T170-10A10 software Filipine 335-42008-00 LCD panel 203-L42T170-13 100-L42T170-13 INC4218 301-CPS42D8-14A RC-C14-0A remote control (INSIGNIA) 615-10626-00 stand ASS'Y (DZ-1642S） 615-20456-01 speaker ASS'Y ( LEFT) 615-20457-01 speaker ASS'Y ( RIGHT) 667-L37T7-01 MAIN PCB ASS'Y 667-L42K17-20 POWER PCB ASS'Y (42"CMO) 667-L42T17-05 KEY BOARD ASS'Y 667-L42T17-09 IR RECEIVE ASS'Y 667-L47T17-55 high frequency BOARD ASS'Y KEY1 HDCP SL37T70-01B10 software 37T7mega8 SL37T70-01C10 software 37T7HDMIEDID SL37T70-01D10 software 37T7VGAEDID SL42T170-13A10 software 42T17 335-42008-00 LCD panel 203-L42T170-14 100-L42T170-14 LC-42T17 301-IL37T25-04C RC-I04-0C remote control (ME) 535-L42T17-00 hanging assemble 615-10626-00 stand ASS'Y (DZ-1642S） 615-20548-00 SPEAK ASS'Y 667-L37T7-01 MAIN PCB ASS'Y 667-L42K17-20 POWER PCB ASS'Y (42"CMO) 667-L42T17-05 KEY BOARD ASS'Y 667-L42T17-09 IR RECEIVE ASS'Y 667-L42T17-55 high frequency BOARD ASS'Y KEY1 HDCP SL37T70-01B10 software 37T7mega8 SL37T70-01C10 software 37T7HDMIEDID SL37T70-01D10 software 37T7VGAEDID SL42T170-12A10 software 42T17OSD 335-42008-00 LCD panel 203-L42T170-15 KEY1 HDCP 100-L42T170-15 LC-42T17 301-IL37T25-04A RC-I04-0A remote control PRIMA 535-L42T17-00 hanging assemble 615-10626-00 stand ASS'Y (DZ-1642S） 615-20548-00 SPEAK ASS'Y 667-L37T7-01 MAIN PCB ASS'Y 667-L42K17-20 POWER PCB ASS'Y (42"CMO) 667-L42T17-05 KEY BOARD ASS'Y 667-L42T17-09 IR RECEIVE ASS'Y 667-L42T17-55 high frequency BOARD ASS'Y SL37T70-01B10 software 37T7mega8 SL37T70-01C10 software 37T7HDMIEDID SL37T70-01D10 software 37T7VGAEDID SL42T170-15A10 software 335-42008-00 LCD panel 203-L42T170-17 100-L42T170-17 FLM-4201 301-DL42T17-02A RC-D02-0A remote control (POLAROID) 535-L42T17-00 hanging assemble 615-10626-00 stand ASS'Y (DZ-1642S） 615-20548-00 SPEAK ASS'Y 667-L37T7-01L MAIN PCB ASS'Y 667-L42T17-05 KEY BOARD ASS'Y 667-L42T17-09 IR RECEIVE ASS'Y 667-L42T17-20 POWER PCB ASS'Y (42"LGT BOARD ) 667-L42T17-55A high frequency BOARD ASS'Y KEY1 HDCP SL37T70-01B10 software 37T7mega8 SL37T70-01C10 software 37T7HDMIEDID SL37T70-01D10 software 37T7VGAEDID SL42T170-17A10 software NTSC 335-42007-00 LCD panel 203-L47T170-13 100-L47T170-13 LC-47T17 301-IL37T25-04A RC-I04-0A remote control PRIMA 535-L47T17-00 hanging assemble 615-10554-00 stand ASS'Y (DZ-1647) 615-20459-00 speaker ASS'Y ( LEFT) 615-20460-00 speaker ASS'Y ( RIGHT) 667-L37T7-01 MAIN PCB ASS'Y 667-L42T17-09 IR RECEIVE ASS'Y 667-L42T17-55 high frequency BOARD ASS'Y 667-L47K17-20 POWER PCB ASS'Y (47"CMO) 667-L47T17-05 KEY BOARD ASS'Y KEY1 HDCP SL37T70-01B10 software 37T7mega8 SL37T70-01C10 software 37T7HDMIEDID SL37T70-01D10 software 37T7VGAEDID SL47T170-13A10 software CMO47 335-47001-00 LCD panel 207-LM47T170-10 100-LM47T170-10 FLM-4701 301-DL42T17-02A RC-D02-0A remote control (POLAROID) 615-10554-01 stand ASS'Y (DZ-1647) 615-20459-00 speaker ASS'Y ( LEFT) 615-20460-00 speaker ASS'Y ( RIGHT) 667-L37T7-01A MAIN PCB ASS'Y 667-L42T17-09 IR RECEIVE ASS'Y 667-L42T17-55A high frequency BOARD ASS'Y 667-L47T17-05 KEY BOARD ASS'Y 667-L47T17-20 POWER PCB ASS'Y (47"LG) KEY1 HDCP SL37T70-01B10 software 37T7mega8 SL37T70-01C10 software 37T7HDMIEDID SL37T70-01D10 software 37T7VGAEDID SLM47T170-02A10 software LG panel monitorLOGO 335-47002-00 LCD panel 603-L47T17X-XX Ver.1.0 603-L42T17X-XX