Electrical Troubleshooting Guide; Power / Micom / Lcd - LG LAS751M Service Manual

ELECTRICAL TROUBLESHOOTING GUIDE

1. POWER / MICOM / LCD

Does the LED
blinking?
NO
Is L100
Voltage 3.3 V?
NO
Pin3 of IC302
should be 3.7 V.
NO
Pin3 of IC309
should be 25 V.
NO
Pin2 of IC601
should be 25 V.
NO
Check adaptor.
YES
Is R141
low state?
Pin4 of CN400
should be 5 V.
Pin2 of IC301
should be 5.3 V.
Does IC308 work?
L312 should be 25 V.
YES
Replace micom (IC100).
YES
Replace IC302.
YES
Replace IC309.
YES
Replace IC601.
2-23
YES
NO
YES
NO
YES
NO
YES
NO
Replace micom (IC100).
Replace LCD.
Replace IC301.
Replace IC308.