Troubleshooting Guide - LG FLATRON W1954TQ Service Manual

NO POWER
(POWER INDICATOR OFF)
CHECK P704 VOLTAGE
1
PIN5, PIN6 (5V)?
2
IS IC704 PIN1(3.3V)
IC704 PIN4(1.8V)
1 3
CHECK U501 PIN127
1 4
CHECK U501
Waveforms
1
P704-#5,6
Copyright 2007 LG Electronics. Inc. All right reserved.
Only for training and service purposes

TROUBLESHOOTING GUIDE

1. NO POWER
YES
YES
PULSE
YES
2
IC704-#2
NO
NO
NO
3
IC704-#2
- 15 -
CHECK POWER BOARD,
AND FIND OUT A SHORT
POINT AS OPENING
EACH POWER LINE
CHECK IC704(3.3V)
IC704(1.8V) LINE
CHECK CRYSTAL(X501)
4
U501-#127
LGE Internal Use Only