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Checking the backlight unit
Is +12V supplied to inverter
PWB? (input from Power Board)
Failure Point:
1. Inverter cable disconnected.
2. Power board is failure.
Check the BL_ENABLE
signal of the rectangle input P301 pin2
at TTL high level
NG
OK
Failure Point:
1. Printed wire open between R305 and I306 pin49.
2. R305 is open or short.
3. I306 is failure.
NG
OK
Check the BKLT_ADJ
signal of the input P301 pin3 from
I306 pin50 is a PWM signal
NG
Failure Point:
Backlight unit of LCD module is failure.
OK
Failure Point:
1. Printed wire is open between P301 pin3 ,R304, Q301,
R301, R302 and I306 pin50.
2. R304,Q301,R301 or R302 is failure.
3. I306 is failure.
Appendix 4: Troubleshooting
Go to cover page
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ACER AL2002W