Philips 50PFL4909/F7 Service Manual page 27

[Video Signal Section]
FLOW CHART NO.1
The key operation is not functioning.
Yes
Replace the Digital Main CBA Unit.
FLOW CHART NO.2
No operation is possible from the remote control unit. (Operation is possible from the unit.)
Yes
Yes
Replace the Digital Main CBA Unit.
FLOW CHART NO.3
Picture does not appear normally.
Yes
Yes
No
Replace the Function CBA Unit.
No
Check AL+3.3V line and repair it if defective.
No
Replace the IR Sensor CBA Unit.
No
See FLOW CHART NO.5 <P-ON+21V is not output.
[Power Supply Section]>
No
See FLOW CHART NO.7 <AL+3.3V is not output.
[Power Supply Section]>
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