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3-4
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Only for training and service purposes
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No 12VT
Check D127 on SMPS
Board and Replace
YES
YES
NO
Is the VCC (14V)
supplied to Q164 Collector?
Check Q164 and Replace
YES
NO
Is there about 12.5V at
ZD151 & Q164 Base?
Check D128 on SMPS
Board and Replace
YES
NO
Is the VCC (33V)
supplied to Q162 Emiter?
Check Q162 and Replace
YES
NO
Is there about 0V at
Q162 Base?
Check the “TIMER_H”
signal from µ-COM
YES
NO
Is there
about 5V at R181 and 0.7V at
Q155 Base?
Check Q152 and Replace
2. POWER SUPPLY ON I/O BOARD
ELECTRICAL TROUBLESHOOTING GUIDE