LG NP5550W - Electrical Troubleshooting Guide; Power Dsp; Amp

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ELECTRICAL TROUBLESHOOTING GUIDE
1. POWER DSP/ AMP
Power DSP
Connect CN901.
Replace IC500.
Replace IC901.
Replace IC903.
OK
Charge the battery.
Check connection of CN901.
IC500 is voltage of 1.8 VA? (pin56)
Is voltage of SYS_PWR
3.3 V ~ 4.2 V? (IC903 pin5)
3V3 is voltage of 3.3 V? (FB901)
Is voltage of the battery
above 3.3 V? (CN901)
NO
NO
NO
NO
NO
YES
YES
YES
YES
YES
Power AMP
Connect CN700.
Replace IC902.
OK
Charge the battery.
Check connection of CN700.
Does 5 V or 9 V flow
IC700 (check pin12 ~ 14)?
Is voltage of the battery
above 3.3 V? (CN901)
NO
NO
NO
YES
YES
YES