Panasonic TC-55CX650U

[JayArr_BC]

Hi All

I've got this 55" that flashes on power up but then goes dark.

The red indicator light comes on steady when I apply power and the screen flashes on and I can see a graphics box that says something (looks like a typical blue on grey Panasonic message box) then th screen goes off (lamps off) and the indicator light begins a sequence of a single flash followed by a one second pause.

I've attached pics of all the boards and I've started with the main board, I have 5V on the SRV-5V test point but nothing on SRV-16V and SRV-400V can be as high as 210 but continues to drop, as if it was on it's way to 400V when shutdown occurred and is now bleeding off.

Since I can briefly see a picture with a defined graphic can I assume that my main board and TCon are OK?

I pulled the lines that go to the lamps off the second power supply board but the aymptoms didn't change so I don't think it's a short or problem with the lamps.

Does anyone have suggestions and or a service manual?

Thanks
JayArr

[JayArr_BC]

Re: Panasonic TC-55CX650U

OK, I got this one fixed. Turns out it was a couple of lamps and I learned something new.

I thought that if I had bad lamps that by removing the connectors to the backlights I would remove the problem and the set should come on without a backlight. Not so with this unit. Unplugging the backlights actually causes a 'one blink' error. I guess the PB board is watching for both shorted strips and open strips. There are two ICs for the 9 strips and each strip of LEDs has it's own transistor to turn them on.

So I had two bad LEDs and they caused a 'one blink' error and then I unplugged the backlights and still got a one blink error and went looking elsewhere. See how I got confused?

Pulled it all apart and replaced the two LEDs on two different strips and it's running like a champ.

One note: I used the shop jimmy LED tester to turn on the lamp strips and this is what eventually led me to the problem, all strips lit, but two of them lit at 60V and the other seven lit at 49. This little tool has paid for itself a few times now, if you don't own one consider adding it to your next shop jimmy order.

[budm]

Re: Panasonic TC-55CX650U

Service manual:

[Deathact]

Re: Panasonic TC-55CX650U

I am having the same problem on a TH-60CX700A. Just wondering where you got your back lights from.