Power Led Blinking Timing Chart; Lcd Panel Test Mode - Panasonic TC-L42U30 Service Manual

6.2.

Power LED Blinking timing chart

1. Subject
Information of LED Flashing timing chart.
2. Contents
When an abnormality has occurred the unit, the protection circuit operates and reset to the stand by mode. At this time, the
defective block can be identified by the number of blinks of the Power LED on the front panel of the unit.
6.3.

LCD Panel test mode

Purpose:
To find the possible failure point where in LCD Panel or Printed Circuit Board when the abnormal picture is displayed.
How to Enter:
While pressing [VOLUME ( - )] button of the main unit, press [SUB MENU] button of the remote control three times within 2
seconds.
How to Exit:
Disconnect AC plug from wall outlet.
How to confirm:
If the abnormal picture is displayed, go into LCD Panel test mode to display the several test patterns.
And then, judge by the following method.
Still abnormal picture is displayed: The cause must be in LCD Panel or TC board.
Normal picture is displayed: The cause must be in A board.
Remarks:
The test pattern is created by the circuit in TC board.
In LCD Panel test mode, this test pattern is displayed unaffected by signal processing for RF or input signal.
If the normal picture is displayed, LCD Panel or TC board must be okay and the cause of failure must be in A board.
Blinking Times
1 BACK LIGHT SOS
2 SUB 1.8V SOS
3 SUB 1.2V SOS
4 POWER SOS
9 ZWEI2 SOS
10 SUB 3.3V SENSE
12 SOUND SOS
Contents
16
Check point
LCD PANEL
P-Board
A-Board
A-Board
A-Board
P-Board
TC-Board
A-Board
A-Board
Speaker