Troubleshooting; Electrical Trouble Shooting Guide; Power (Dc-Dc Converter) Circuit - Sony DVP-FX850 Service Manual

9-1. ELECTRICAL TROUBLE SHOOTING GUIDE

1. A. Power (DC-DC Converter) circuit
No power on
by adaptor
YES
NO
Is adaptor
Replace adaptor
out 9.5V?
YES
NO
Is P1 OK? Replace P1
YES
NO
Is D2 OK? Replace D2
YES
NO. P_3V3
YES
NO
Is Q12 OK? Replace Q12
YES
NO
Is U6 OK? Replace U6
B. Audio out abnormal
AUDIO OUT ABNORMAL
Check audio jack & mode
YES
Check U19
YES
Check U17
YES
Check U18
YES
NO
Check signals from
U7 (MT1389)
SECTION 9

TROUBLESHOOTING

No power on
by battery
YES
Is battery OK?
YES
Is Q1 OK?
YES
NO. +3.3V
YES
NO
Is U5 OK? Replace U5
YES
NO. +1.8V
YES
NO
Is U4 OK? Replace U4
C. Speaker abnormal
SPEAKER ABNORMAL
Is S1, S2 OK?
YES
Is speaker OK?
YES
Is U14 OK?
YES
Replace U7
9-1
NO
Replace battery
NO
Replace Q1
NO. +5V
YES
NO
Is U2 OK? Replace U2
YES
NO
Is –AVCC
Replace U15
OK?
NO
Replace S1, S2
NO
Replace speaker
NO
Replace U14
DVP-FX850
NO.
LCD power
YES
NO
Is U1 OK? Replace U1
YES
NO
Is –USB VCC
Replace U21
OK?