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DigiMedia
Service Manual
LCD TV For LT26HVX
Doc. No.：
Version：1.0
Total Pages：34
Approvals
Job Function Signature Date
CPO
Project Manager
R&D Dept. Manager
EE Dept. Manager
ME Dept. Manager
Engineering Dept. Manager
Sales Dept. Manager
Quality Assurance Dept. Manager
Author
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TITLE
Service Manual
LCD TV For LT26HVX
Table of Contents
1 Introduction……..…………..……………………………………… P3
1.1 Preface……………………………..……………………………………………… P3
1.2 Caution…………………………………..…...…………………………………… P3
1.3 W arning…………………………………………..………………………………. P3
2 System Block Diagram…………………………………………….. P4
2.1 System Block Diagram……………………………………………………………
2.2 Connector Connection Diagram………………………………………………….
2.3 Connector Pin Definition………………………………………………………...
3 Troubleshooting…………………………………………………….
3.1 No Power…………………………………………………………………………
3.2 No Sound…………………………………………………………………………
3.3 No Source Input……………………………………………………………………
3.4 Keypad Failed……………………………………………………………………
3.5 IR Failed……………………………………………………………………………
P4
P5
P6
P21
P21
P22
P23
P24
P25
4 Firmware upgrade applications……………………………………P26
5 Disaggregate Graphic………………………………….…………
P28
5.1 TV Tuner and Interface Module…………………………………………………
5.2 Stand Module………………………………………………………………...……
5.3 Back Cover………………………………………………………………………...
5.4 System Board…………………………..………….………………………………
5.5 Keypad Board……………………………………………..……...…...…………..
5.6 Speaker…………………………………………………..…………………….…..
5.7 Power Module…………....………………………………………………………..
5. LCD Panel Module………….……………………………..………………………
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P28
P29
P30
P31
P32
P32
P33
P34
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TITLE
Service Manual
LCD TV For LT26HVX
1. Introduction
1.1 Preface
This service manual aims directly at the module of LCD TV. It offers the simple repair which
emphasizes on technique explanation and production troubles to remove for the engineers and
technicians who have electronic background.
1.2 Caution
Be sure to read those ma nual before s ervicing. To assure safety from fire, electric shock, injur y,
harmful radiation and materials, various measures are provided in this Digimedia LCD TV. Be
sure to read cautionary items described in the manual to maintain safety before servicing.
1.3 Warning
1. Remember to unplug the AC cord from the AC outlet before cleaning the product. And do
not use liquid cleaners or aerosol cleaners to clean the display.
2. Do not place the product on an unstable place. It can c ause the product to fall, resulting in
serious personal injuries as well as damage to the product.
3. In case the product needs replacement parts, make sure that the service person uses
replacement parts specified b y the manufacturer, or those with the same characteristics and
performance as the original parts. Use of unauthorized parts can result in fire, electric shock
and/or other danger.
4. Do not overload AC outlets or extension cords. It can cause fire or electric shock.
5. The AC cords must be routed properly to preven t people from stepping on them or objects
from resting on them. Check the cords at the plugs and product.
6. Do not hit the panel. Be careful to prevent from getting hurt by broken glass pieces in case
the panel breaks.
7. Keep the product away from heat sources such as radiators, heaters, stoves and other
heat-generating products.
8. Do not place the display near water. Like bathtub, washbasin, kitchen sink and laundry tub,
swimming pool and in a wet basement.
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2. System Block Diagram
2.1 System block diagram
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2.2 Connector Connection Diagram
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2.3 Connector Pin Definition
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SYSTEM BOARD
Function: VGA Signal In port
Connector type : D-Sub
Specification: CNNT-HD D Sub-H-F-3Row-15pin-Dip-BLU
Pin Definition
Pin No. Pin Name I/O Description
1 VGAR I 75 ohm termination, 0.7Vp-p red signal
2 VGAG I 75 ohm termination, 0.7Vp-p green signal
3 VGAB I 75 ohm termination, 0.7Vp-p blue signal
4 GND - GND 5 NC - No connection
6 GND - GND
7 GND - GND
8 GND - GND
9 VGA5V I VCC 5V IN
10 GND - GND
11 GND - 12 VGASDA I/O I2C data bus for Reading DDC data
13 VGA_HS I Horizontal Sync.
14 VGA_VS I Vertical Sync.
15 VGASCL I I2C clock bus for Reading DDC data
Function: DVI signal port
Connector type : DVI
Specification: CNNT-DVI-H-29PIN-1.9mm-1.5A-WHITE-dip
Pin Definition
Pin No. Pin Name I/O Description
1 RX2m I TMDS LVDS input signal
2 RX2p I TMDS LVDS input signal
3 GND - GND
4 NC - No connection
5 NC - No connection
6 DDC_CLK I I2C clock bus for Reading DDC data
7 DDC_DATA I/O I2C data bus for Reading DDC data
8 NC - No connection
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9 RX1m I TMDS LVDS input signal
10 RX1p I TMDS LVDS input signal
11 GND - GND
12 NC - No connection
13 NC - No connection
14 GDC5V VCC 5V
15 GND GND
16 HOTPLG VCC 5V
17 RX0m TMDS LVDS input signal
18 RX0p TMDS LVDS input signal
19 GND GND
20 NC - No connection
21 NC - No connection
22 GND GND
23 RXCp TMDS LVDS input clock
24 RXCm TMDS LVDS input clock
25 NC - No connection
26 NC - No connection
27 NC - No connection
28 NC - No connection
29 AGND - GND
30 AGND - GND
Function: PC Audio In
Connector type: RCA
Specification: CNNT-RCA white/red -F DIP RIGHT ANGLE 8.3ψ-4PIN
Pin Definition
Pin No. Pin Name I/O Description
1 GND - GND
2 AUD_R I Audio In_R
3 GND - GND
4 AUD_L I Audio In_L
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Function: RS-232 port
Connector type: Mini Din
Specification: CNNT-Mini Din-H-F-８pin-12ψ-Dip
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Pin Definition
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Pin No. Pin Name I/O Description
1 NC - No connection
2 FlsahDL# I Cable Plug In Detect
3 GND - GND
4 NC - No connection
5 NC - No connection
6 P_DGNS# - Download Function Control
7 PC_TXD O RS-232 Data Transmit
8 PC_RXD I RS-232 Data Receive
9 GND - GND
10 GND - GND
11 GND - GND
Function: Keypad In
Connector type: M15-I20001
Specification: CNNT M 15PIN pitch 2.0mm DIP Straight WST(blue)
Pin Definition
Pin No. Pin Name I/O Description
1 NC - NC
2 LED_B1 O Signal for Indicator LED
3 LED_B1 O Signal for Indicator LED
4 LED_B1 O Signal for Indicator LED
5 GND - GND
6 IRD I IR Data In
7 GND - GND
8 KEY_Y3 I Signal sent from Keypad to System 3
9 KEY_Y2 I Signal sent from Keypad to System 2
10 KEY_Y1 I Signal sent from Keypad to System 1
11 KEY_X3 O Signal sent from System to Keypad 3
12 KEY_X2 O Signal sent from System to Keypad 2
13 KEY_X1 O Signal sent from System to Keypad 1
14 GND - GND
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15 V5_IR O 5V POWER Out
Function: TUNER IN /AV IN
Connector type: BOARD TO BOARD
Specification: 2-557100-1 CNNT-Dip Right Angle-M - 80PIN-1.27mm-0.5A(Board to Board)
Pin Definition
Pin No. Pin Name I/O Description
1 CHKTNR1 I CHECK AV Board In
2 V5_TUNER O POWER OUT_5V
3 V5_TUNER O POWER OUT_5V
4 GND - GND
5 GND - GND
6 NC - No connection
7 NC - No connection
8 NC - No connection
9 NC - No connection
10 GND - GND
11 HD_PR I HD_PR In
12 HD_PB I HD_PB In
13 HD_Y I HD_Y In
14 SV_SEL1 O S_Video_SEL
15 GND - GND
16 ALO_SC2 O Scart2 AUDIO_L CH out
17 ARO_SC2 O Scart2 AUDIO_R CH out
18 ALO_SC1 O Scart1 AUDIO_L CH out
19 ARO_SC1 O Scart1 AUDIO_R CH out
20 GND - GND
21 YCBCR_L O YCBCR AUDIO_L CH out
22 YCBCR_R O YCBCR AUDIO_R CH out
23 HDTV_L O HDTV_L AUDIO_L CH out
24 HDTV_R O HDTV_L AUDIO_R CH out
25 GND - GND
26 SIF1_IN I SIF format _IN1
27 SIF2_IN I SIF format _IN2
28 GND - GND
29 IF_TU2CVBS I Tuner2 CVBS IN
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30 IF_TU1CVBS I Tuner1 CVBS IN
31 GND - GND
32 V12_SYS2 O +12V OUT
33 NC - No connection
34 NC - No connection
35 V12_SYS2 O +12V OUT
36 PC2DTV_TX I PC TO DTV_TX IN
37 PC2DTV_RX I PC TO DTV_RX IN
38 S2DTV_TX I SYS TO DTV_TX IN
39 S2DTV_RX I SYS TO DTV_RX IN
40 RESETn I RESET
41 GND - GND
42 CVBS_SC1 I CVBS1 IN
43 IF_YCVBS I S-VIDEO1_Y In
44 IF_C I S-VIDEO1_C In
45 GND - GND
46 OCVBS_SC2 O Scart2 cvbs out
47 IF_CR I YCBCR_CR IN
48 IF_CB I YCBCR_CB IN
49 IF_Y I YCBCR_Y IN
50 GND - GND
51 DTV_PR I DTV_ Pr In
52 DTV_PB I DTV_ Pb In
53 DTV_Y I DTV_ Y In
54 TPA_MODE I CHECK EARPHONE CONNECT In
55 EPOUT_L O Audio EARPHONE L CH OUT
56 EPOUT_R O Audio EARPHONE R CH OUT
57 AMP_WF O Audio Sub woofer OUT
58 LINE_L O Audio Line L CH out
59 LINE_R O Audio Line R CH out
60 GND - GND
61 SAL_SC2 I Audio CVBS2/SV2 L ch in
62 SAR_SC2 I Audio CVBS2/SV2 R ch in
63 CVBSAL_SC1 I Audio CVBS1/SV1 L ch in
64 CVBSAR_SC1 I Audio CVBS1/SV1 R ch in
65 GND - GND
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66 SCL O Software I2C Clk
67 SDA I/O Software I2C data
68 HWSDA I/O hardwae I2C data
69 HWSCL O hardwae I2C clk
70 GND - GND
71 CVBS_SC2 I CVBS2 IN
72 IF_YCVBS2 I S-VIDEO2_Y In
73 IF_C2 I S-VIDEO2_C In
74 ADC2 I A/D conver
75 DTV_L I Audio DTV L ch in
76 DTV_R I Audio DTV R ch in
77 ADC1 I A/D conver
78 DTV_SPDIF I DTV audio format
79 ADC0 I A/D conver
80 DTV_IR I DTV_IR pin
Function: LVDS output port
Connector type: TD01-30R1
Specification: CNNT-LVDS-F SMD STRAIGHT-V-30 PIN-1.25mm
Pin Definition
Pin No. Pin Name I/O Description
1 NC - No connection
2 GND - GND
3 NC - No connection
4 NC - No connection
5 NC - No connection
6 GND - GND
7 GND - GND
8 GND - GND
9 TXE3P O Positive LVDS differential data output
10 TXE3N O Negative LVDS differential data outpu
11 TXECKP O Positive LVDS differential clock out
12 TXECKN O Negative LVDS differential clock ou
13 GND - GND
14 GND - GND
15 TXE2P O Positive LVDS differential data output
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16 TXE2N O Negative LVDS differential data output
17 TXE1P O Positive LVDS differential data output
18 TXE1N O Negative LVDS differential data output
19 TXE0P O Positive LVDS differential data output
20 TXE0N O Negative LVDS differential data output
21 GND - GND
22 GND - GND
23 GND - GND
24 GND - GND
25 GND - GND
26 VCC - +5.0V power supply
27 VCC - +5.0V power supply
28 VCC - +5.0V power supply
29 VCC - +5.0V power supply
30 VCC - +5.0V power supply
Function: Power Input 1
Connector type:M15-I25002
Specification:
CNNT M 15PIN pitch 2.5mm DIP straight
Pin Definition
Pin No. Pin Name I/O Description
1 +V5_SYS I DC Power 5V IN
2
+V5
I DC Power 5V IN
3 +V5 I DC Power 5V IN
4 +V5 I DC Power 5V IN
5 +V5 I DC Power 5V IN
6 GND - GND
7 GND - GND
8 GND - GND
9 GND - GND
10 +V5 I DC Power 5V IN
11 GND - GND
12 LCD_INVON O Inverter On/Off
13 PWSTBY O Standby Mode Power 5V
14 BRI O Backlight Brightness Control
15 GND - GND
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Function: Power Input 2
Connector type:M11-I25002
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Specification: CNNT M 11PIN pitch 2.5mm DIP straight
Pin Definition
Pin No. Pin Name I/O Description
1 +V12 I DC Power 12V IN
2
+V12
I DC Power 12V IN
3 +V12 I DC Power 12V IN
4 GND - GND
5 GND - GND
6 GND - GND
7 +12V I DC Power 12V IN
8 GND - GND
9 +12V I DC Power 12V IN
10 GND - GND
11 GND - GND
Function: Audio Out (R Channel)
Connector type:M3-I25002
Specification: CNNT M 3PIN pitch 2.5mm DIP straight red
Pin Definition
Pin No. Pin Name I/O Description
1
R_OUTN
O Negative Audio Out_R
2 NC - No connection
3 R_OUTP O Positive 0Audio Out_R
Function: Audio Out (L Channel)
Connector type: M3-I25002
Pecification : CNNT M 3PIN pitch 2.5mm DIP straight white
Pin Definition
Pin No. Pin Name I/O Description
1
L_OUTN
O Negative Audio Out_L
2 NC - No connection
3 L_OUTP O Positive 0Audio Out_L
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AV BOARD
Function: TUNER OUT / AV OUT
Connector type: BOARD TO BOARD
Specification: 2-557100-1 CNNT-Dip Right Angle-M - 80PIN-1.27mm-0.5A(Board to Board)
Pin Definition
Pin No. Pin Name I/O Description
1
CHKTNR1
O CHECK AV Board In
2 V5_TUNER I POWER IN_5V
3 V5_TUNER I POWER IN_5V
4 GND - GND
5 GND - GND
6 NC - No connection
7 NC - No connection
8 NC - No connection
9 NC - No connection
10 GND - GND
11 HD_PR O HD_PR OUT
12 HD_PB O HD_PB OUT
13 HD_Y O HD_Y OUT
14 SV_SEL1 I S_Video_SEL
15 GND - GND
16 ALO_SC2 I Scart2 AUDIO_L CH IN
17 ARO_SC2 I Scart2 AUDIO_R CH IN
18 ALO_SC1 I Scart1 AUDIO_L CH IN
19 ARO_SC1 I Scart1 AUDIO_R CH IN
20 GND - GND
21 YCBCR_L I YCBCR AUDIO_L CH IN
22 YCBCR_R I YCBCR AUDIO_R CH IN
23 HDTV_L I HDTV_L AUDIO_L CH IN
24 HDTV_R I HDTV_L AUDIO_R CH IN
25 GND - GND
26 SIF1_OUT O SIF format _OUT1
27 SIF2_OUT O SIF format _OUT2
28 GND - GND
29 IF_TU2CVBS O Tuner2 CVBS OUT
30 IF_TU1CVBS O Tuner1 CVBS OUT
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31 GND - GND
32 V12_SYS2 I +12V IN
33 NC - No connection
34 NC - No connection
35 V12_SYS2 I +12V IN
36 PC2DTV_TX O PC TO DTV_TX OUT
37 PC2DTV_RX O PC TO DTV_RX OUT
38 S2DTV_TX O SYS TO DTV_TX OUT
39 S2DTV_RX O SYS TO DTV_RX OUT
40 RESETn O RESET
41 GND - GND
42 CVBS_SC1 O CVBS1 OUT
43 IF_YCVBS O S-VIDEO1_Y OUT
44 IF_C O S-VIDEO1_C OUT
45 GND - GND
46 OCVBS_SC2 I Scart2 cvbs IN
47 IF_CR O YCBCR_CR OUT
48 IF_CB O YCBCR_CB OUT
49 IF_Y O YCBCR_Y OUT
50 GND - GND
51 DTV_PR O DTV_ Pr OUT
52 DTV_PB O DTV_ Pb OUT
53 DTV_Y O DTV_ Y OUT
54 TPA_MODE O CHECK EARPHONE CONNECT OUT
55 EPOUT_L I Audio EARPHONE L CH IN
56 EPOUT_R I Audio EARPHONE R CH IN
57 AMP_WF I Audio Sub woofer IN
58 LINE_L I Audio Line L CH IN
59 LINE_R I Audio Line R CH IN
60 GND - GND
61 SAL_SC2 O Audio CVBS2/SV2 L ch OUT
62 SAR_SC2 O Audio CVBS2/SV2 R ch OUT
63 CVBSAL_SC1 O Audio CVBS1/SV1 L ch OUT
64 CVBSAR_SC1 O Audio CVBS1/SV1 R ch OUT
65 GND - GND
66 SCL I Software I2C Clk
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67 SDA I/O Software I2C data
68 HWSDA I/O hardwae I2C data
69 HWSCL I hardwae I2C clk
70 GND - GND
71 CVBS_SC2 O CVBS2 OUT
72 IF_YCVBS2 O S-VIDEO2_Y OUT
73 IF_C2 O S-VIDEO2_C OUT
74 ADC2 O A/D conver
75 DTV_L O Audio DTV L ch OUT
76 DTV_R O Audio DTV R ch OUT
77 ADC1 O A/D conver
78 DTV_SPDIF O DTV audio format
79 ADC0 O A/D conver
80 DTV_IR O DTV_IR pin
Function: S-Video1 1/2 In
Connector type: Mini Din
Specification: CNNT F 12PIN Mini Din DIP Right Angle 12ψ AMP( 2 S-Video)
Pin Definition
Pin No. Pin Name I/O Description
1 GND - GND
2 GND - GND
3 S1AV_C2 I S-Video1_C2 In
4 S1AV_Y2 I S-Video1_Y2 In
5 GND - GND
6 GND - GND
7 S1AV_C1 I S-Video1_C1 In
8 S1AV_Y1 I S-Video1_Y1 In
9 GND - GND
10 GND - GND
11 GND - GND
12 GND - GND
13 GND - GND
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Function: CVBS 1/2 and CVBS 1/2 AUDIO 1/2 In
Connector type: RCA
Specification: CNNT-RCA*6 yellow & white & red / yellow & white & red
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Pin Definition
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Pin No. Pin Name I/O Description
1
CVBS1
I CVBS1 In
2 CVBS1_AR I CVBS1 Audio_R In
3 CVBS1_AL I CVBS1 Audio_L In
4 CVBS2 I CVBS2 In
5 CVBS2_AR I CVBS2 Audio_R In
6 CVBS2_AL I CVBS2 Audio_L In
7 GND - GND
8 GND - GND
9 GND - GND
Function: Earphone Out
Connector type: PHONE JACK
Specification: CNNT-EAR Phone Jack-H-F-5pin-3.6ψ-Dip
Pin Definition
Pin No. Pin Name I/O Description
1 EAR_ROUT O EAR Audio_R OUT
2 GND - GND
3 TPA_MODE O TPA_MODE
4 EAR_LOUT O EAR Audio_L OUT
5 GND - GND
Function: Audio Output Port (Line Out)
Connector type: RCA
Specification: CNNT-RCA*2 white / red
Pin Definition
Pin No. Pin Name I/O Description
1 GND - GND
2 LINE_R O Audio Line_R Out
3 GND - GND
4 LINE_L O Audio Line_L Out
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Function: Component 1/2 (YPbPr1/YcbCr1) In
Connector type: RCA
Specification: CNNT-RCA*6 green & blue & red / green & blue & red
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Pin No. Pin Name I/O Description
1 COM1_Y I Component1_Y In
2 COM1_Pb I Component1_Pb In
3 COM1_Pr I Component1_Pr In
4 COM2_Y I Component2_Y In
5 COM2_Cb I Component2_Cb In
6 COM2_Cr I Component2_Cr In
7 GND - GND
8 GND - GND
9 GND - GND
Function: Component 1/2 Audio 1/2 In
Connector type: RCA
Specification: CNNT-RCA*4 white & red / white & red
Pin Definition
Pin No. Pin Name I/O Description
1 COM1_AL I Component1 Audio_L In
2 COM1_AR I Component1 Audio_R In
3 COM2_AL I Component2 Audio_L In
4 COM2_AR I Component2 Audio_R In
5 GND - GND
6 GND - GND
Function: Digital Tuner Out
Connector type:MD32-I20003
Specification: CNNT M 32pin (16x2) pitch 2.0mm DIP straight
Pin Definition
Pin No. Pin Name I/O Description
1 V5_TUNER O POWER OUT_5V
2 +12V O POWER OUT_12V
3 V5_TUNER O POWER OUT_5V
4 +12V O POWER OUT_12V
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5 GND - GND
6 GND - GND
7 S2DTV_TX I SYS TO DTV_TX IN
8 RESETn O RESET
9 S2DTV_RX I SYS TO DTV_RX IN
10 MAIN_DE I MAIN_DE pin
11 GND - GND
12 GND - GND
13 PC2DTV_TX I PC TO DTV_TX IN
14 SCL I Sofeware I2C Clk
15 PC2DTV_RX I PC TO DTV_RX IN
16 SDA I/O Sofeware I2C data
17 GND - GND
18 GND - GND
19 DTV_Y I DTV_Y In
20 DTV_SPDIF I DTV audio format
21 GND - GND
22 DTV_SPDIF I DTV audio format
23 DTV_Pb I DTV_Pb In
24 GND - GND
25 GND - GND
26 DTV_L I Audio DTV L ch I
27 DTV_Pr I DTV_Pr In
28 DTV_R I Audio DTV R ch I
29 DTV_DL I DTV_DL pin
30 DTV_IR I DTV_IR pin
31 DTV_NM I DTV_NM pin
32 GND - GND
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KEYPAD BOARD
Function: Keypad In
Connector type: M15-I20001
Specification: CNNT M 15PIN pitch 2.0mm DIP Straight WST
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Pin Definition
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Pin No. Pin Name I/O Description
1
NC
- NC
2 LED_B1 I Signal for Indicator LED
3 LED_B1 I Signal for Indicator LED
4 LED_B1 I Signal for Indicator LED
5 GND - GND
6 IRD O IR Data Out
7 GND - GND
8 KEY_Y3 O Signal sent from Keypad to System 3
9 KEY_Y2 O Signal sent from Keypad to System 2
10 KEY_Y1 O Signal sent from Keypad to System 1
11 KEY_X3 I Signal sent from System to Keypad 3
12 KEY_X2 I Signal sent from System to Keypad 2
13 KEY_X1 I Signal sent from System to Keypad 1
14 GND - GND
15 V5_IR I 5V POWER In
Function: Indicator Out
Connector type: M3-I20001
Specification: CNNT M 3PIN pitch 2.0mm DIP Straight WST
Pin Definition
Pin No. Pin Name I/O Description
1
V5_Indicator
O 5V POWER Out
2 LED_B1 I Signal for Indicator LED
3 GND - GND
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N
LCD TV For LT26HVX
3. Troubleshooting
3.1 No Power
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Check power plug is
securely inserted into the
power socket?
Yes
1. Check power to system cable
2.Check system to keypad cable
3.Check power to panel cable
4.Check keypad and remote
control power key connector
insert?
Power plug is
o
securely inserted
into the power
socket.
o
Please replace the
cable what cause the
power on failed.
Yes
If power on still failed, please replace power module.
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N
N
3.2 No Sound
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Check the speaker wire
connector to system
board?
Yes
Check the input source
and audio cable into the
correct connector?
Please connection
o
the speaker wire to
system board.
Confirm input
o
source and audio
cable select to the
correct channel.
Yes
1. Keep OSD is not in mute mode.
2. Confirm the volume value is not 0.
3. Power off, and re-plug power socket again.
4. If items 1,2 and 3 have no problem, replace
interface board or system board.
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N
N
LCD TV For LT26HVX
3.3 No Source Input
RGB or video source can’t be found
Service Manual
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Check OSD select
correct?
Yes
Check image signal input
at system board or
interface board?
Confirm input
o
source and the
output of OSD select
is correct.
Check input source
o
cable connection
into the connector.
Yes
Replace system board or interface board.
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3.4 Keypad Failed
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LCD TV For LT26HVX
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Keypad no response
1. Check the cable of keypad to system board.
2. Check keypad function.
3. If item 1 and 2 have no problem, please replace
keypad board or system board.
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N
N
N
3.5 IR Failed
Service Manual
LCD TV For LT26HVX
IR no response
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Check F/W vision?
Yes
Check remote control
has energy?
Yes
o
o
Reinstall F/W .
Change remote
control battery.
Check keypad board
connection into system
board?
o
Please connection
the keypad board
into system board.
Yes
Replace Keypad or remote control or
system board.
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4. Firmware upgrade applications
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1. Update Firmware tools：
1.PC(Notebook)
2. transmission line as Figure1
3.Sofeware(
MtkTool.exe , COMPR.DLL ,
MTKDLL.DLL)
Figure1
2. Cable switch: on D side (refer Figure2)
Figure2
3. Insert the power cord and RS232 cable.
4. Insert RS232 cable in Mouse socket or RS232 socket(refer Figure3) and other side insert to
service socket on TV(refer Figure4 and Figure5)
Figure3
Figure4
Figure5
5. There are some files should be in directory. (MtkTool.exe , COMPR.DLL , MTKDLL.DLL)
Figure6
6. Execute MtkTool.exe.(step 6 and step 7 please refer Figure 6)
7. Make sure IC model is MT8205, serial connection is correct(default is COM1) and baud rate
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TITLE
Service Manual
LCD TV For LT26HVX
is 115200.
8. Click the Browse of “Load Bin file option” to choose the correct firmware.
9. Click the bottom of Upgrade, System will start upgrade firmware, when it fished the operation,
list form has to show the “Finished” as blow arrow (step 8 and step 10 please refer the
Figure7)
10. pull out the RS232 cable and AC cord.
Figure7
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5. Disaggregate Graphic
5.1 Interface Module
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LCD TV For LT26HVX
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1. Loosen 4 screws as red circles.
2. Pull the Interface module to the right
side and pull up as blue arrow.
3. Loosen 5 screws as red circles.
4. Loosen Tuner nut as blue circles.
5. Loosen 4 screws as red circles.
6. Take apart AV cover metal and
Interface Board
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5.2 Stand Module
Service Manual
LCD TV For LT26HVX
1. Loosen 7 screws as red circles.
2. Take apart the Stand Module.
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3. Loosen 7 screws as red circles.
4. Take apart the Stand Cover and Stand
5. Loosen 4 screws as blue circles.
6. Take apart the Stand Bottom Metal and
Stand Support Metal.
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5.3 Back Cover
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1. Please finish the step 5.1 and 5.2 to take apart
the Interface module and Stand Module first.
2. Loosen 11 screws as red circles.
3. Take apart the Back Cover and TV.
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5.4 System board
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Figure1
Figure2
1. Please loosen 8 screws as red circles of Figure1, the screw locations are around the
Shielding, every side has 2 screws.
2. Loosen 1 screw as blue circles of Figure2.
3. Take apart the shailding.
4. Please pull out of all wires.
5. Loosen 4 screws as red circles.
6. Take apart the System Board.
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5.5 Keypad board
1. Please loosen 5 screws as red circles.
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2. Take off all of connector as blue circle.
5.6 Speaker
Right side
Left side
1. You need pull out of speaker wire with System board connector.
2. Please directly take apart the Speaker.
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TITLE
Service Manual
LCD TV For LT26HVX
5.7 Power Module
.
1. Please pull out the power wires with Panel Inverter connector and System board
connector as red arrows of Figure1 and Figure2.
Figure1 Figure2
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LCD TV For LT26HVX
5.8 LCD panel module
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1. Loosen 10 screws as blue
circles.
2. Loosen 4 screws as red circles.
3. Loosen 4 screws as blue arrows and blue circles.
4. If you take off the System Board and Power Supply before, you can direct take apart the Panel
5. Careful to take panel one
side up as blue arrow.
6. Pull out the LVDS wire and Power wire.
7. Take apart the Panel Module.
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