Electrical Troubleshooting Guide; Power/Dsp/Amp - LG NP7550 Service Manual

ELECTRICAL TROUBLESHOOTING GUIDE

1. POWER/DSP/AMP

Power/DSP
Check connection
of CN901.
Is voltage
of the battery above 6.5 V?
(CN901)
Is voltage
of IC902 3.4 V?
Is the input voltage
3.4 VA? (L501)
Is the input voltage
1.2 VA? (L509)
OK
Power/ AMP
Check connection
of CN901.
Is voltage
of the battery above 6.5 V?
(CN901)
Does 13 V flow IC700?
(Check pin2, 3, 34, 35.)
OK
NO
YES
NO
YES
NO
YES
NO
YES
NO
YES
NO
YES
NO
YES
NO
YES
Charge the battery.
Charge the battery.
3-7
Connect CN901.
Replace IC902.
Replace L501.
Replace L509.
Connect CN901.
Replace IC907.