LG CJS98F - Electrical Troubleshooting Guide

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ELECTRICAL TROUBLESHOOTING GUIDE
1. POWER SUPPLY ON SMPS BOARD
YES
YES
YES
YES
YES
No output 5.1 VA
No 12 V
Power line of MAIN PCB is short.
Replace F901 (same fuse).
Check or replace D963.
Is D960, D961 normal?
Replace BD901.
Check P_CTL from μ-com.
Check IC951 and replace.
Or
check line of MAIN PCB is short or not.
Check or replace D960, D961.
NO
NO
NO
NO
NO
Is the F901 normal?
Is the
VCC 12 VA supplied to IC951
pin1?
Is the VCC
(11 V ~ 25 V) supplied to IC901
pin4?
Is BD901 normal?
Is there
‘HIGH’ signal at IC951
pin4?