Service manual

ManualsBrandsAOC ManualsComputer equipmente2250Sw

21.5" LCD Monitor AOC e2250Sw

Service

Horizontal Frequency

30 - 83kHz

Table of Contents

Description Page Description Page

SAFETY NOTICE

ANY PERSON ATTEMPTING TO SERVICE THIS CHASSIS MUST FAMILIARIZE HIMSELF WITH THE

CHASSIS AND BE AWARE OF THE NECESSARY SAFETY PRECAUTIONS TO BE USED WHEN SERVICING

ELECTRONIC EQUIPMENT CONTAINING HIGH VOLTAGES.

Table of Contents…………………..…………………..…...1

Revision List.…...................................................……......2

Important Safety Notice.….….............................……......3

1.Monitor Specification..............................………............4

2.LCD Monitor Description……….…………………….......5

3.Operation Instruction.…………...................……...........6

3.1.General Instructions....................................…...........6

3.2.Control Buttons and Connections...............................6

3.3.OSD Setting…..........................................................8

4.Input/Output Specification...............……………….......24

4.1.Input Signal Connector...............………..................24

4.2.Preset Display Modes……..........................25

4.3.Panel Specification…………..………………………..26

5.Block Diagram….........................................................29

5.1.Main Board…..….............................................29

5.2.Power Board…………..…………………………......30

6.Schematic…………..….........................................31

6.1.Main Board..…….…...........................................31

6.2.Power Board..……….........................................35

7.PCB Layout..………..............................................37

7.1.Main Board………..…........................................37

7.2.Power Board….…..............................................39

7.3.Key Board………..…..........................................40

8.Maintainability………............................................41

8.1.Equipments and Tools Requirement…...............41

8.2.Trouble Shooting…..………...............................42

9. FOS Testing………………………………………46

10.Firmware and DDC Instruction……………….….50

11.White-Balance,Luminance Adjustment…............61

12.Mechanical Instructions …............ ..............63

13.Monitor Exploded View……................................71

14.BOM List…………..……………………….............72

CAUTION: USE A SEPARATE ISOLATION TRANSFOMER FOR THIS UNIT WHEN SERVICING

Summary of content (78 pages)

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21.5" LCD Monitor AOC e2250Sw Service Service Service Horizontal Frequency 30 - 83kHz Table of Contents Description Page Description Page Table of Contents…………………..…………………..…...1 6.1.Main Board..…….…...........................................31 Revision List.…...................................................……......2 6.2.Power Board..……….........................................35 Important Safety Notice.….….............................……......3 1.Monitor Specification...........................
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Revision List Version Release Date Revision History TPV Model Name TIBARV2QAGA42NE A00 Jun.
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Important Safety Notice Proper service and repair is important to the safe, reliable operation of all AOC Company Equipment. The service procedures recommended by AOC 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. The special tools should be used when and as recommended.
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1.
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2.LCD Monitor Description The LCD monitor will contain a main board, a Power board and a key board which house the flat panel control logic, brightness control logic and DDC. The power part will provide AC to DC Inverter voltage to drive the backlight of panel and the main board chips each voltage. Monitor Block Diagram LED Drive.
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3. Operating Instructions 3.1 General Instructions Press the power button to turn the monitor on or off. The other control knobs are located at front panel of the monitor (See Figure ). By changing these settings, the picture can be adjusted to your personal preferences. * The power cord should be connected. * Press the power button to turn on the monitor. The power indicator will light up. 3.2 Control Buttons and Connections Power Press the Power button to turn on/off the monitor.
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1. Power 2. Analog (DB-15 VGA cable) To protect equipment, always turn off the PC and LCD monitor before connecting. 1 Connect the power cable to the AC port on the back of the monitor. 2 Connect one end of the 15-pin D-Sub cable to the back of the monitor and connect the other end to the computer's D-Sub port. If your monitor displays an image, installation is complete. If it does not display an image, please refer Troubleshooting.
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3.3 OSD Setting Basic and simple instruction on the control keys. 1) Press the MENU-button to activate the OSD window. 2) Press - or + to navigate through the functions. Once the desired function is highlighted, press the MENU-button to activate it . press - or + to navigate through the sub-menu functions. Once the desired function is highlighted, press MENU-button to activate it. 3) Press - or + to change the settings of the selected function. Press AUTO to exit.
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Luminance 1 (Menu) to display menu. Press 2 Press or to select (Luminance), and press to enter. 3 Press or to select submenu, and press or to adjust. 4 Press to enter.
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5 Press two times to exit.
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Image Setup 1 Press (Menu) to display menu. 2 Press or to select (Image Setup), and press 3 Press or to select submenu, and press or to adjust. to enter. 4 Press 11 to enter.
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5 Press two times to exit.
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Color Setup 1 Press (Menu) to display menu. 2 Press or to select (Color Setup), and press to enter. 3 Press or to select submenu, and press or to adjust. to enter.
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5 Press two times to exit.
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Picture Boost 1 Press (Menu) to display menu. 2 Press or to select (Picture Boost), and press or to select submenu, and press or to adjust. 3 Press to enter. 4 Press 15 to enter.
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5 Press two times to exit.
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OSD Setup 1 Press (Menu) to display menu. 2 Press or to select (OSD Setup), and press or to select submenu, and press or to adjust. 3 Press to enter. 4 Press 17 to enter.
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5 Press two times to exit.
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Extra 1 Press (Menu) to display menu. 2 Press or to select (Extra), and press to enter. 3 Press or to select submenu, and press to enter. 4 Press or to adjust.
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5 Press two times to exit.
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Exit 1 Press (Menu) to display menu. 2 Press or to select (Exit), and press to enter.
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LED Indicators Status LED Color Full Power Mode Green or Blue Active-off Mode Orange or red e-Saver Welcome to use AOC e-Saver monitor power management software! The AOC e-Saver features Smart Shutdown functions for your monitors, allows your monitor to timely shutdown when PC unit is at any status (On, Off, Sleep or Screen Saver); the actual shutdown time depends on your preferences (see example below). Please click on "driver/e-Saver/setup.
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Question e-sensor no power interface show e-sensor it can’t your monitor to turn off or dark while you are away Answer 1. Into the factory mode，set Burn in to OFF; 2. Set e-sensor to ON. The detecting range is too near or far and the User is far away the monitor, reset the examination area. 1. Please do not block the e-Sensor on the LOGO, which is located on the left of AOC logo. 2. The detecting range is too far or the things blocks monitor , reset the examination area.
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4. Input/Output Specification 4.
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4.
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4.3 Panel Specification 4.3.1 General Features The M215HW01 model is a 21.5 inch wide TFT-LCD module with LED Backlight Unit and a 30-pin 2ch-LVDS interface. This module supports 1920 x 1080 Full HD (16:9 wide screen) mode and displays up to 16.7 millions colors. All input signals are 2-channel LVDS interface . 4.3.2 GENERAL SPECIFICATIONS 4.3.3 Electrical Characteristics Electrical characteristics Note 1: Measurement conditions: The duration of rising time of power input is 470us.
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Note 1: LVDS Signal Waveform 27
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LED array electrical characteristics Note (1) The LED can work normally if the PWM dimming ratio range is from 0% to 100% and the operation current is 60mA. Note (2) PLED = (ILED ×4) × VLED , LED matrix is 15S4P.The lightbar used by backlight unit. Note (3) The lifetime of LED is defined as the time when it continues to operate under the conditions at Ta = 25 ±2℃ and I = 60 mA(Per EA) until the brightness becomes ≤50% of its original value.
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5. Block Diagram 5.1 Main Board XGA/SXGA CMVCC1 LVDS OUTPUT DSUB_R+ DSUB_RDSUB_G+ DSUB_GDSUB_SOG DSUB_B+ DSUB_BDSUB_H DSUB_V DDC1_SDA DDC1_SCL DET_CABLE DSUB_R+ DSUB_RDSUB_G+ DSUB_GDSUB_SOG DSUB_B+ DSUB_BDSUB_H DSUB_V DDC1_SDA DDC1_SCL DET_CABLE EDID_CTRL EDID_CTRL VCC1.2 VCC3.3 VCC1.2 VCC3.3 CMVCC1 CMVCC1 CMVCC1 02.Input 04.Output VCC1.2 VCC3.3 VCC1.2 CMVCC PA[0..1] on_BACKLIGHT VCC3.
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5.2 Power Board AC input EMI filter Bridge Rectifier and Filter Transformer (T901) Rectifier diodes 14.5 5V Start Resistor (R908,R911) PWM Control LD7576AGR (U901) Feedback Circuit Power Switch (Q901) Photo coupler (U902) 14.
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6. Schematic 6.1 Main Board 715G4737M01BRA004C FB102 H_Sy nc V_Sy nc R101 0R05 1/10W R102 100R 1/16W 5% R103 100R 1/16W 5% R105 2K2 1/16W 5% DSUB_H DSUB_V VGA_B+ 5 5 1 BEAD R104 2 R107 R106 C102 C103 2K2 1/16W 5% 22PF 50V 22PF 50V C101 100R 1/16W 5% C104 75 OHM +-5% 1/16W VGA_B- 5PF 50V R108 5 10 4 9 3 8 2 7 1 6 14 ミΑCONN 13 DSUB_SDA 12 DSUB_5V VGA_B+ VGA_BVGA_G+ VGA_GVGA_R+ VGA_R- C106 22NF25V 1K 1/16W 5% ZD103 FB103 VGA_G+ 1 RLZ5.
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U402 SST Eon For user data, WB, EDID, HDCP are saved in Flash. VCC3.3 AVDD VCC1.2 6 Eon U402 For All model 3 3 3 3 3 3 3 3 3 3 3 13 12 10 9 11 8 7 16 17 18 19 DSUB_R+ DSUB_RDSUB_G+ DSUB_GDSUB_SOG DSUB_B+ DSUB_BDSUB_H DSUB_V DDC1_SDA DDC1_SCL R+ RG+ GSOG0 B+ BHSY NC0 VSY NC0 DDCA_SDA/RS232_TX DDCA_SCL/rs232_RX 7 DVDD12 DVDD12 For ID2008 ID2009 PVDD33 Befor AOC ID2007 OSD 020A ADC_VDD33 010A 020 51 U402 30 53 VCC3.
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5 PANEL_VCC PA[0..1] PA[0..1] PA0 PA1 5 CN405 for 18.5" panel (single LVDS PANEL_VCC channel) PA[4..9] PA[4..9] PA4 PA5 PA6 PA7 PA8 PA9 5 R434 300 OHM 1/4W C420 100N16V 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 L/T_SDA PA1 PB3 PA5 PA7 PA9 PB1 PB3 PB5 PB7 PB9 PB0 PB1 PB2 PB3 PB4 PB5 PB6 PB7 PB8 PB9 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 L/T_SDA L/T_SCL PA0 PA1 PB2 PB3 PA4 PA5 CN405 PB[0..9] PB[0..
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2008/01/14 BAT99 : If 0.05A,VF=1.0V BAV70 : If 0.05A,VF=1.0V It's need to use Low Dropout Regulator. CMVCC 5 CMVCC1 CN404 9 8 7 6 5 4 3 2 1 VCC3.3 VCC3.3 VCC3.3 CMVCC CMVCC1 R450 NC NC(R0402) 5 R449 PANEL_ID# 5 R437 R439 NC 10K 1/16W 5% 10K 1/16W 5% C425 NC NC Mute VCC1.2 R479 NC/0R05 1/4W BKLT-EN CMVCC1 CMVCC CMVCC BKLT-VBRI BKLT-EN C_PANEL_INDEX Volume Mute R480 1.5 OHM +-5% 2WS R465 VCC1.
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6.2 Power Board 715G4744P01000001C ! 1 R929 100 OHM 1/4W C916 R930 100 OHM 1/4W 2N2 500V C928 2N2 500V F801 0R05 1/4W +14.
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1 +14.5V 1 2 SK310B C810 0.47UF 50V S1 G1 S2 G2 R801 10K 1/8W + R814 10 OHM 1% 1/4W C809 2 1 2 3 4 ON/OFF R802 300K 1/8W R805 C802 10N 50V FB801 BEAD 1 100K 1/8W R818 10K 1/8W DIM R803 300K 1/8W C803 1N 50V C815 CN801 5 4 3 2 1 R806 1N 50V C806 220N 50V 1 OHM +-5% 1/8W VIN VREF STATUS LDR SSTCMP ISW PWM ENA ISEN1 RT ISEN2 OVP GND ISET ISEN3 ISEN4 R808 1 OHM +-5% 1/8W R819 R820 R821 NC NC NC R822 NC NC/CONN C811 33UF 100V 0.47UF 50V R817 100 OHM 1/4W C813 100PF 50V R812 0.
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7. PCB Layout 7.
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7.
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7.
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8. Maintainability 8.1 Equipments and Tools Requirement 1. Voltmeter. 2. Oscilloscope. 3. Pattern Generator. 4. DDC Tool with an IBM Compatible Computer. 5. Alignment Tool. 6. LCD Color Analyzer. 7. Service Manual. 8. User Manual.
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8.2 Trouble Shooting 1.
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2.
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3.
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4.
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9. FOS Testing 9.1 Brightness Measurement Max. Brightness>250 cd/㎡(typ). Test conditions: - Center of display - Video input (RGB) = 0,700V for Analog Input - Brightness control is set to max - Contrast control is set to max. Min. brightness measurement: < 45% of Max luminance (max luminance = max contrast + max brightness) Test conditions: - Center of display - Video input (RGB) = 0.700V for Analog Input - Brightness control is set to min. - Contrast control is set to min. 9.
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Cross line Half line H-Line V-Line H-Strip 1. 1920 x 1080 (60 Hz) 2. Black pattern 1. 1920 x 1080 (60 Hz) 2. Black pattern or White pattern 1. 1920 x 1080 (60 Hz) 2. Black pattern, Red pattern, Green pattern or Blue pattern. 1. 1920 x 1080 (60 Hz) 2. Black pattern or White pattern 1 1920 x 1080 (60 Hz) 2. Black pattern, Gray scale pattern, Red pattern, Green pattern or blue pattern .
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V-Strip 1. 1920 x 1080 (60 Hz) 2. Black pattern, Gray scale pattern, Red pattern, Green pattern or blue pattern . Abnormal display 1. 1920 x 1080 (60 Hz) 2. Gray scale pattern Gray defect 1. 1920 x 1080 (60 Hz) 2. Gray scale pattern Video noise 1. 1920 x 1080 (60 Hz) 2. Gray scale pattern Color tint 1. 1920 x 1080 (60 Hz) 2.
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Gray scale failure Light leakage Fuzzy video 1. 1920 x 1080 (60 Hz) 2. Gray scale pattern 1. 1920 x 1080 (60 Hz) 2. Black pattern or White pattern 1. 1920 x 1080 (60 Hz) 2.
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10. Firmware and DDC Instruction 11. Firmware and DDC Instruction 10.1Firmware Instruction(TSUM IC ISP for exemple Milo Qw1904e) Step 1:Tool list： 1. ISP board715GT034-B. 2. Printer cable and VGA cable 3. Adapter cable(12V) 4. Two three-core cables Reference picture as below： Step2: Software list： 1. LPT driver 2. Realtek_ISP_Tool_V2.2 Step3: Setup Software and Connection： 1. Setup LPT driver:run Port95nt icon: 2.
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3. double-click Realtek_ISP_Tool_V2.2 。 Step4: Program： 1. Run realtek_ISP_Tool_V2.2,interface as below: 2.
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3. Click “Flash Protect” and interface show dialog box，in turn, choice Value→High；Series→LPA series；Pin List→Pin28；Click “OK”。 4.
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5.
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6. Show the interface as follows after press the icon： 7. It’s successfully if interface show PASS.
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10.2 DDC Instruction（For exemple：Philips 201B） Tool list: 1. DDC board:715GT034-B 2. Software (WA.DAT&WD.DAT&*. CONFIG.INI) 3. LPT driver software 4. LPT cable, D-SUB CABLE 5. 12V( Adapter) 6. TPVDDCHDMI and TPVDDC6.0 7. PC 8.
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Tool picture For VGA BURNING: DDC Board as the follow picture: TO PC LPT DC 12V power VGA Install software: Double-click the icon “ VGA Burning: 1. Double-click “ ” to install Port95nt print driver, and then restart the computer. ”, select “Analog ” show as follow picture.
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2. Click “Load file” and select as follow picture.
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3. Click “ok” show as follow picture. 4.Input same SN twice and date. Click “Pragram” to burn. When appear “pass” as follow picture that burning is successful.
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5.Click “READ” show as follow picuture.If read SN is same as before inputing and model name is same as before that burning is successful.
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Appear fault as follow, please check the connection of LPT cable , Tool adapter cable and LCD power. . Note: If the burn software is unsuccessfulll, appear fault： 1. For VGA,the resolution will be not the best achieve. 2. For HDMI,No picture，no sound. If program failed, in VGA mode, you can’t use the optimal resolution. When Read is OK, program is NG, pls do take following action: 1. For VGA,cut off the 9th pin (connect the monitor). 2. For DVI, cut off the 14th pin (the shortest pin, power supply). 3.
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11.White- Balance, Luminance Adjustment Approximately 30 minutes should be allowed for warm up before proceeding white balance adjustment. How to setting MEM channel you can reference to chroma 7120 user guide or simple use “SC” key and “NEXT” Key to modify xyY value and use “ID” key to modify the TEXT description Following is the procedure to do white-balance adjust . 1. Setting the color temp. A. 6500K: Warm color temp. parameter is x=313±30 ，y=329±30 B. 7300K Normal color temp.
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C. Adjust Cool (9300K) color-temperature 1. Switch the Chroma-7120 to RGB-Mode (with press “MODE” button) 2. Switch the MEM. Channel to Channel 9 (with up or down arrow on chroma 7120) 3. The LCD-indicator on chroma 7120 will show x=283±30，y=297±30 4. Adjust the RED on factory window until chroma 7120 indicator reached the value R=100 5. Adjust the GREEN on factory window until chroma 7120 indicator reached the value G=100 6.
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12.Mechanical Instructions 1. Put the monitor on the EPE pad. 2. Lay down the monitor and the bottom side faces to Yourself.
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3. Pinch the hook and remove the base. 4. Use fixture to leave off the stand.
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5. Use fixture to remove the hinge cover. 6. Remove the screws of the stand.
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7. Remove the screws of the back cover. 8. Overturn the monitor and the top towards to yourself, and then take apart the front frame with hands.
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9. Prize up the front frame use fixture. 10. Overturn the monitor and take off the back cover.
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11. According to the different defective area to take off the KEPC, light line, LVDS, Hexagon screws, CBPC or PWPC to repair. （1）Remove the KEPC. （2）Pull the light line out.
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（3）Remove the Hexagon screws. （4）Remove the LVDS.
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（5）Overturn the iron plate and remove the screws, PWPC and CBPC.
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12.
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14. BOM List Note: The parts information listed below are for reference only, and are subject to change without notice. Please go to http://cs.tpv.com.cn/hello1.asp for the latest information. TIBARV2QAGA42NE Location E08902 E08902 E08901 E08907 E09504 E09504 E09504 E750 E08907 Part No.
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CN408 CN404 CN403 CN101 X401 LED001 CN001 U402 U402 SMTCB-U402 GND1 U902 NR901 C908 C903 C902 C900 C907A C907 C809 C801 C918 C922 L901 L906 L801 T901 CN901 D902 D901 CN902 CN902 CN804 BD901 C421 C423 C426 C427 R002 R004 R001 R003 Q901 033G3802 6B Y L 033G3802 9B Y L 033G801930F CH JS 088G 35315FVCL 093G 2253B J 709G4737 HM001 H40G 45762429A KEPCAHB5K 081G 12 1F GP 095G820H 6TE10 709G4747 HM002 756GHBCB A1020 056G2233 11 056G2233501 100GARAI000Z11 009G6005 1 056G 139 3A 061G 5810T 063G107K474 6S 065G305M
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HS1 HS3 D906 U901 U801 Q801 RJ801 R811 R804 R916 R806 R907 R801 R818 R928 R918 R805 R808 R807 R815 R810 R920 R919 R803 R802 R809 R905 R816 R925 F801 R917 R814 R910 R903 R909 R930 R929 R912 R911 R908 R913 R813 R812 R923 R902 R901 R900 R817 C813 C812 090G6064 1 0M1G 930 8120 090G6084 1 GP 093G 60507 0M1G 930 8120 055G 23524 Q51G 6 4509 Q55G 100625 056G 379529 056G 700 11 057G 763 92 061G0805000 JF 061G0805000 JF 061G0805100 JF 061G08051002FT 061G0805102 JF 061G0805102 JT 061G0805103 JF 061G0805103 JF 061G08
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C923 C914 C803 C815 C906 C915 C802 C814 C924 C912 C926 C806 C807 C927 C811 C810 C804 C808 C929 C928 C917 C916 D801 U401 U406 U103 U102 U405 U402 Q404 Q402 Q403 Q406 Q407 Q410 Q409 Q405 R481 R402 R401 R412 R413 R420 R411 R405 R117 R115 R114 R111 R108 R104 R103 R102 R109 065G080510232K 065G080510232K 065G080510232K 065G080510232K 065G080510232K 065G080510332K 065G080510332K 065G080510432K 065G080510432K 065G080510432K 065G080510432K 065G080522432K 065G080522432K 065G080547332K 065G080547432K 065G080547432K 0
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R442 R435 R437 R439 R440 R441 R487 R433 R414 R410 R408 R118 R436 R492 R491 R490 R489 R105 R106 R466 R469 R474 R403 R421 R427 R428 R475 R476 R485 R473 R472 R107 R112 R116 R101 R468 R471 R479 R434 R477 C436 C432 C428 C422 C420 C419 C417 C416 C415 C414 C413 C407 C406 C403 C401 061G0402102 JT 061G0402103 JT 061G0402103 JT 061G0402103 JT 061G0402103 JT 061G0402103 JT 061G0402103 JT 061G0402103 JT 061G0402103 JT 061G0402103 JT 061G0402103 JT 061G0402104 JT 061G0402104 JT 061G0402220 JT 061G0402220 JT 061G0402220
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C404 C412 C411 C102 C103 C106 C408 C434 C113 C110 C109 C107 C105 C101 C104 C108 C111 FB402 FB401 FB102 FB103 FB101 D403 ZD103 E715 E715 SW005 SW004 SW003 SW002 SW001 E715 C805 C816 C911 C913 D903 F901 F902 FB801 FB802 FB901 FB902 FB903 R924 Q904 J801 J802 J803 J804 J805 J806 J807 J808 065G0402105A5K A 065G040220031J Y 065G040220031J Y 065G040222031J A 065G040222031J A 065G040222322K T 065G040222415K T 065G040222415K T 065G040247312K A 065G040247312K A 065G040247312K A 065G040247312K A 065G040247312K A 065G
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J809 J810 J811 J812 J813 J814 J815 J901 J902 J903 J904 J905 J906 J907 J909 J910 J921 CN901 IC903 R915 R906 R904 C920 ZD901 D907 J908 D904 095G 90 23 095G 90 23 095G 90 23 095G 90 23 095G 90 23 095G 90 23 095G 90 23 095G 90 23 095G 90 23 095G 90 23 095G 90 23 095G 90 23 095G 90 23 095G 90 23 095G 90 23 095G 90 23 095G 90 23 006G 31500 056G 158 10 T 061G 17222052T TZ 061G152M10452T SY 061G152M25152T SY 067G 2046812KT 093G 39A6852T 093G 6452452T 095G 90 23 709G4744 HA001 715G4744P01000001C 093G 6026T52T JUM