LG BPM55 - Electrical Troubleshooting Guide

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ELECTRICAL TROUBLESHOOTING GUIDE
No 3.3 V
Check IC151 and replace.
Is the
Vcc supplied to D150
anode?
Check 5.1 VA on IC150 pin10.
YES
YES
NO
Is D150 output 5.1 VA?
Is there
signal at IC151
pin1?
Check C178 or replace D150.
Check voltage on IC501.
YES
YES
NO
NO
No 5 V
Check IC150 and replace.
Is the
Vcc 5.3 VA supplied to IC150
pin27?
Is there
3.3 V at IC150
pin25?
Check 5.1 VA on IC150 pin10.
Check PWR_CTL2 signal from IC501.
YES
YES
YES
NO
NO
1. POWER SUPPLY ON MAIN BOARD