(1) When the set turns on and a picture appears, the bottom of
the picture shows the Input selection screen.
The Remote did not work.
(2) The panel indicates a brief flash during start up, then “No
Picture”
PICTURE APPEARS WITH SELECTION SCREEN AT THE BOTTOM
The Front Function Keys did not work. (Except the Main Power
Switch)
* Main Board: Reading the Key 1 and Key 2 lines found that
Key 2 was at 0.8V. Key 1 read normal at 3.3V.
* Feeling the Function buttons found that the right hand
button (as viewed from the rear) did not feel the same as the others. It was
stuck.
Remove and re-position the button assembly.
A brief flash at start-up, but no picture.
* Z-SUS does not produce a correct signal. (All voltages
check normal except 17V).
* Y-SUS does not produce a correct signal. (No negative
portion).
* On Y-SUS: 17V starts off at 17V then very quickly drops
to 5V.
* Floating Ground 5V and 15V are not produced.
* Removing all connectors on the Z-SUS board (Except the
panel connectors) does not change test results.
* Removing Y-Drive boards cause all voltages to return to
normal. Including the Y-Drive signal checked on the right side of C213.
* Reconnecting all connectors on the Z-SUS board shows it
is not creating a correct waveform. Just spikes. (17V now stays up).
* Using the Diode Checks for the Y-Drive boards do not
indicate a problem.
Replace the Z-SUS board.
BACK COVER REMOVAL