3-7
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Only for training and service purposes
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No SW_5.3VA
Is the Vcc (5.3V)
supplied to Q158 emiter?
Check 5.3VA on SMPS board
YES
YES
NO
Is there about 0V
at R179 and R156?
Check the “STANBY H”
signal from µ-COM
YES
NO
Check Q158 and replace
No SW_FD(+)
Is the Vcc (FD+) supplied
to Q163 collector?
Check D121 on SMPS
board and replace
YES
YES
NO
Is there about 5.3V at
R184 and Q153 collector?
Check Q163 and replace
YES
NO
Is the VCC (5.3V)
supplied to Q153 emiter?
Check 5.3VA on SMPS board
YES
NO
Is there about 0V
at Q153 base?
Check the “STANBY H”
signal from µ-COM
YES
NO
Check Q153 and replace