3-2
ELECTRICAL TROUBLESHOOTING GUIDE
1. Power check flow
No 3.4VA.
No 3.4VA
Is 3.4VA section working?
Is 3.4V present at emitter
of Q121?
Replace Q121.
Replace IC101.
Is there a DC voltage at
Cathode of D105 or D107?
Check FR101
No 5V
Is 3.4VA section working?
Replace Q126.
Is 5.6V present at collector
of Q126?
NO
YES
YES
YES
YES
Check D105/D106/D107/
D108 and replace.
YES
YES
A.
B.
NO
NO
NO
