LG LCD TV Troubleshooting – No back-light – No power – No startup - Service tips

LG LCD TV – Repair Tips – Faults and Checks

LG 32LE2RZJ Chassis LP61A LCD TV
Symptom: Remotes control no functions at all.
> Replace SMD capacitor at output of IR receiver.

LG 37LE2R Chassis LP61A LCD TV
Symptom: No start-up.
> Replace SMD regulator TL431 (U130) in PSU.

LG 32LC45 LCD TV
Symptom: "No Signal" displayed. No sound and no picture. Backlight and
OSD menu is ok. LED is green color light.
> Try to update firmware if not then replace main signal board.

LG 47LY95 Chassis LD75A LCD TV
Symptom: Negative picture and no sound.
Voltage output low at pin 7 of connector P202.
> Check Q202 (AP72T02GH), U203 (APU3037M), Q203 (AP60T03GH) and connector P202 in PSU. Also check or replace C221, C222, C223 and C232.

LG 47LF66 LCD TV
Symptom: No power
> Change the C202, C206 and C217 (all 2200uf/10v) on IP board (Inverter Power Supply Board).

LG 37LF66 LCD TV
Symptom: No power
IC U500 (ICE3B1565J) is short circuit and fusible resistor FB501 (2.2R) open circuit.
> Check safety resistor for open circuit. Replace D501 (UF4007), 3.6v Zener diode ZD502 (1N5227) and C508 (33uF/50v).

LG 32LC56ZC LCD TV
Symptom: No start-up. Standby LED flashes from red to green
> Check or replace C202, C206, C217, C218 (all 2200uF/10v) and C226 (470uF/25v).

LG 32LC56 LCD TV
Symptom: Picture divided into several parts. Distorted picture
> Replace T-CON (Part Number: 218394).

LG 32LC56ZC LCD TV
Symptom: Stuck in standby mode.
> Check & change C204. If the pcb board discolored around R208 resistor then replace PSU.
LG Chassis LA73A LCD TV
32LB4DS-UA, 32LB9D-UA, 32LB4DS-UA, 37LB5DF-UC, 42LB5DF-UC, 47LB5DF, 47LC7DF-UB, 47LY3DF-UA, 52LB5DF-UC
Symptom: a) Auto Power on and Power Off
b) Auto Channel Up and Down
c) Auto OSD Menu display
> Check or replace EMI filter on these location: L729, L730, L741, L742, L743, L744, L746, L747, L751, L752, and L753.

LG 42LK520-UA, 42LK530-UA, 42LK550-UA LCD TV
Symptom: When power on the LCD TV, there is no display
Cause: Because the Height of embo is low, when assembling C/PCB to the module, it can have a scratch on the bottom on T-con board.
- Thermal pad press the C/PCB
- PCB bottom (scratch point) is short with C/Bottom (Ground)
- Because of the over-current, it will make the mainboard damage.
> Temporary solution is to add isolation cushion sheet between Embo and C/PCB.

LG 32LG700H, 37LG700H & 42LG700H LCD TV
Power itself On/Off.
Cause: Touch IC sensor malfunction
> IR assembly C104 change from 2pF to 12pF.
LG LC370W01-A5K1 T-con Board
Symptom: Grey Screen, No display
> This T-con board Vin is use 12V as input voltage. Found their Vcc input SMD fuse KT opened and looks like other components has shorted in the circuits. Measure the Vin line ohm values is normal. After that checking the other voltage output lines ohm values and found that VDD with GND has 0 ohm! That’s mean something was shorted to ground. Finally found that C130 filter cap was short circuit. After replace SMD fuse KT and C130 filter cap, the TV is back to normal.

LG LC420W02-B6 LCD Panel with 6870C-0046B T-con Board
Symptom: Screen Show Negative Display with Full Red Color
> The LVDS cable is ok. For this type of display symptom, you must try to slowly minimum the Contrast feature. If after minimum or closed the feature of Contrast and display back to normal (have colors), that’s mean, the problem was in the T-con board and it is causing by timing control not working properly. If after minimum the Contrast feature, the display is missing color, so the problem was in the mainboard. Since this is T-con board problem, so concentrate to testing it. Normally if Timing Control section work, it must have: 1) Correct Vcc input (from DC-DC section supply), 
2) Panel setting (this setting data was store in the EEPROM IC), 
3) Data communication EEPROM with Timing Control IC must stable. 
4) If the Timing Control IC defective it also can effected. Their voltage input is normal and corresponding components also no problem. So try to find another junk board to remove both EEPROM U2 & U5 (both 24Y02) to this T-con board. After power on the TV, yes the problem solved.

LG 27LC2R Chassis LP61A LCD TV
Symptom: No backlight.
> Check the SMD fuse F1 on inverter board for open circuit.

LG 32LC56 LCD TV
Symptom: Picture divided into several parts. Display distortion.
> Replace T-CON board (Part Number: 218394).
LG 32LC56ZC LCD TV
Symptom: No start-up. Standby LED flashes from red to green.
> Replace the C202, C206, C217 and C218 (2200uf/10v all), and C226 (470uf/25v).

LG 37LE2R: No start-up 
LG 37LE2R Chassis LP61A LCD TV
No start-up.
> Replace SMD regulator TL431 (U130) in PSU.

LG 27LC2R: No Backlight 
LG 27LC2R Chassis LP61A LCD TV
No backlight
> Check the SMD fuse F1 on inverter board for open circuit.

LG: No start-up. Standby LED flashes from red to green 
Model/s: LG 32LC56ZC LCD TV
Symptom: No start-up. Standby LED flashes from red to green
> Check or replace C202, C206, C217, C218 (all 2200uF/10v) and C226 (470uF/25v).

LG: Picture divided into several parts. Distorted picture 
LG 32LC56 LCD TV
Symptom: Picture divided into several parts. Distorted picture
> Replace T-CON (Part Number: 218394).

LG: Stuck in standby 
LG 32LC56ZC LCD TV
Symptom: Stuck in standby
> Check & change C204. If pcb board discolored around R208 then replace PSU.

LG: "No Signal" displayed 
LG 32LC45 LCD TV
Symptom: "No Signal" displayed. No sound and no picture. Backlight and OSD menu ok. LED is green color light.
> Try to update firmware if not then replace main signal board.

LG: No Power 
LG 47LF66 LCD TV
Symptom: No power
> Change C202, C206 and C217 (all 2200uf/10v) on IP board (Power Supply Inverter Board).

LG: No Power 
LG 37LF66 LCD TV
Symptom: No power
U500 (ICE3B1565J) short circuit and fusible resistor FB501 (2.2R) open circuit.
> Check safety resistor for open circuit. Replace D501 (UF4007), 3.6v zener diode ZD502 (1N5227) and C508 (33uF/50v).

LG: Negative picture and no sound 
LG 47LY95 Chassis LD75A LCD TV
Symptom: Negative picture and no sound.
Voltage low at pin 7 of connector P202.
Cure/Solutions: Check Q202 (AP72T02GH), U203 (APU3037M), Q203 (AP60T03GH) and connector P202 in
PSU. Also check or replace C221, C222, C223 and C232.

LG 32LG30R-TA LCD TV
Symptom: Stuck in standby mode
> When the AC power on, Red LED light lit. Using remote control to power on the TV, LED light change to Blue color but PSU no 12V, 16.5V & 24V output. PFC big filter capacitor has 380V there. Remove the ZD111, ZD112 & C108 on the PSU board near U102 (NCP1396A). It is a power supply design bugs, so after remove these components, problem solved.