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ELECTRICAL TROUBLESHOOTING GUIDE
No -5 V
Check or replace D967.
Check VFD_PWR_CTRL
From DSP(IC501_C1).
Check or replace Q953, Q957.
Or check line of MAIN PCB is
short or not.
Check or replace Q951.
Is the
VCC -7 VA supplied to IC953
pin2?
Is there
‘H’ signal at Q953
Base?
NO
NO
NO
Is the D967 normal?
YES
YES
YES
No output AMP gate line
Check or replace R9C7, R938.
Check or replace D952, D959.
Check and replace IC952.
Or check line of MAIN PCB is
short or not.
Is the VCC
13 VA supplied to IC952
pin1 to pin3?
NO
NO
Is the
R9C7, R938 normal ?
YES
YES
POWER SUPPLY ON SMPS BOARD