Power Supply On I/O Board - LG RH-2320 Service Manual

2. POWER SUPPLY ON I/O BOARD

No 12VT
YES
Is the Vcc (14V) supplied to
Q164 collector?
YES
Is there about 12.5V at
ZD151 & Q164 base?
YES
Is the Vcc (33V) supplied
to Q162 emiter?
YES
Is there about 0V at
Q162 base?
YES
Is there about 5V at R170
and 0.7V at Q156 base?
YES
Check Q156 and replace
LGE Internal Use Only
NO Check D124 on SMPS
board and replace
NO
Check Q164 and replace
NO Check D126 on SMPS
board and replace
NO
Check Q162 and replace
NO Check the "TIMER_H"
signal from µ-COM
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Only for training and service purposes