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Go to cover page
5. Troubleshooting (continued)
5.3 Checking the back light unit
Is +22V supplied to inverter PWB ? (by the
power board)
Failure Point
NG
1) Power board of Inverter part failure.
OK
Check the BKLT_EN signal of the DC input
P301 pin 1 at TTL high level.
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| 1) printed wire broke between P301 pin1, |
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| NG |
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| OK |
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| R303 and I305 pin 88. | |
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| 2) I305 is failure. |
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Check the BKLT_ADJ signal of the input P301 pin3 from I305 pin86 is a PWM signal.
NG
OK
Failure Point
1) printed wire broke between P301 pin3, R304,R357 and I305 pin11.
2) Q302 is failure.
Failure Point
1)Back light unit of LCD module is failure.
2)Inverter Cable disconnect