Trouble Shooting Guide - LG 40LX770H Service Manual

1. Power-Up Boot Fail Trouble Shooting guide
Check P2300/1 Voltage Level
(13.2V, L2303)
Y
Check IC8701
RESET and UPDATE pin
Y
Check X8700 Clock
32.768KHz
Y
Check IC8701 IIC
communication state
Y
Check IR input state of IC8701
57pin
Y
Re-download PTC Micom
2. No OSD Trouble Shooting guide
Check P2300/1 Voltage Level
(13.2V, L2303)
Check Q2302 output Voltage(13.2V)
Y
Check LVDS Cable
Y
Check LCD Module
Control board
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Only for training and service purposes

TROUBLE SHOOTING GUIDE

Check power connector and RL_ON
N
signal OK ?
(L2030, Pin 1)
N
Check switch SW8700, SW8701
Check X8700 application circuit or
N
Replace X8700
N
Check IIC line or replace IC8701
N
Check IR board
N Check power connector and
RL_ON(pin1) signal OK ?
Check Q2302 application circuit or
N
replace Q2302
N
Replace Cable
- 19 -
Y
Replace Power board
Y
Replace Power board
LGE Internal Use Only