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Text excerpt from page 39 (click to view)
Main PCBs Trouble Diagnosis
7-1-3. When Control Key does not operate
Check Start
N After turn on the power, does LED turn on red light?
1. Check AC connection 2. Check Power S/W ON 3. Check other PCBs
Y
After ST-BY on Does LED turn on green light?
N
Check the connection of KEY PCB to MAIN PCB -> Check the connection between KEY PCB and MAIN PCB
Y
Is output first pin PW7 normal?
N
1. Replace the CON NECTOR 2. Replace KEY PCB
Y
Check Main PCB
A. First check connection, and then check the output of first pin of PA912(ST-BY 3.3V) B. Check waveform first pin and third pin of PA911. If waveform does not appear, replace connector or KEY PCB. -main TP : RC398, RC399
