TCL 55C803 - Powers on, good picture, then shuts off

[R_J]

Re: TCL 55C803 - Powers on, good picture, then shuts off

The cathode of the diodes is the side with the white band. The voltages can't be correct if you are getting the backlights to flash on for a moment. This voltage should be a lot higher
If the anode of D630 goes above 1.7vdc it tells the U601 backlight driver to shut down.

[jason123]

Re: TCL 55C803 - Powers on, good picture, then shuts off

Yes but its a very fast turn on then off the voltage doesn't register on the dmm before it shuts off.

[budm]

Re: TCL 55C803 - Powers on, good picture, then shuts off

What did you use for ground for the meter?

[jason123]

Re: TCL 55C803 - Powers on, good picture, then shuts off

I used the GND pins on one of the edge connectors on the cold side. Tried multiple GND points on the cold side and same results

[budm]

Re: TCL 55C803 - Powers on, good picture, then shuts off

Must be very very slow DMM.

[jason123]

Re: TCL 55C803 - Powers on, good picture, then shuts off

the flash of the backlight, is very quick I think .. DMM doesn't have a max hold feature unfortunately. What is this saying though? I tested the diodes between the transformers and backlight.. caps seem ok.. anything I can try??

[jason123]

Re: TCL 55C803 - Powers on, good picture, then shuts off

Anyone with Schematics for this board so I can understand how it works?
40-L14H4-PWG1CG
08-L141W54-PW210AB

[diif]

Re: TCL 55C803 - Powers on, good picture, then shuts off

Anyone with Schematics for this board so I can understand how it works?
40-L14H4-PWG1CG
08-L141W54-PW210AB

I think you've missed a digit and it's a 40-L141H4-PWG1CG.

[jason123]

Re: TCL 55C803 - Powers on, good picture, then shuts off

I think you've missed a digit and it's a 40-L141H4-PWG1CG.

Thank you.. Yes, I did miss a digit

[jason123]

Re: TCL 55C803 - Powers on, good picture, then shuts off

Ok, general question here for those who know TCL TVs well. This PS came out of a 55C803 TV. It's configured for 4 CH, from what I can see on the schematic. Would you expect the LED1, 2, 3 and 4 paths on the connector to the LEDs to have wires coming out of them? Trying to understand the 2 CH, vs. 4 CH reference on the Schematic.

I got a replacement PS board, and the TV is buttoned up, working fine. I'm testing this PS board on 55S403 setup with the original PS set for 2 channel. So it makes sense that this PS in the 55S403 wouldn't work, right? since 55S403 is a 2-CH setup and this board is configured for 4-Ch