Electrical Troubleshooting Guide; Power (Smps) Circuit - Marantz DV4200 Service Manual

9. ELECTRICAL TROUBLESHOOTING GUIDE

9.1 Power (SMPS) Circuit

A.
No VF+
Is 5.2VA section working?
YES
Is oscillation present at the
anode of D109?
YES
Replace D109.
NO
NO
No 5.2VA.
Check R127, 128.
(SHUTDOWN CKT)
Is 5.2V applied to IC108
Pin 1?
NO
Check Fuse(F101).
YES
Is there a DC voltage at the
(+) terminal of BD101?
YES
Is R111 1Ω?
YES
Check D105.
Replace Q101, 102.
12
B.
No 5V_D
or 5V_A .
NO
Is 5.2VA section working?
YES
NO
Is oscillation present at the
Base of Q108?
YES
Replace Q108.
YES
Check L103, C116.
NO
Replace BD101.
(Bridge rectifier)
NO
Replace R111.