TH-46PZ85U no picture

[dietzcj]

I did mc301 and MC201 fix when I had the 10 blink issue, and it did work, but I am still not getting any video and the power light is solid.
I can see the backlights turning on and it appears the TV IS on. But yet still no video display. I have also replaced the D-Board and I get the same thing.
I certainly hope it is not an A board since these are the one of the more expensive boars on ebay.
I have looked over the service manual
http://www.scribd.com/doc/94280139/P...rts-Th-Nnpz8xu



Any other thoughts ?

[RON_CET]

Re: TH-46PZ85U no picture

Confirm proper connection of the VDA voltage between the power supply, the SS board, and the C board.

[drpj23]

Re: TH-46PZ85U no picture

I believe I had this same prob too (on a different panasonic) and the A board (sorry lol) is most likely responsible for that. This one though had an integrated controller board (d board) but since you replaced that, this is the only thing left. The fact the panel comes on with a steady red light is a good sign though.

[dietzcj]

Re: TH-46PZ85U no picture

Does anyone happen to have TNPH0721ABS (AB being the suffix) "A" board ?

[dietzcj]

Re: TH-46PZ85U no picture

Update:
I reseated all of the cables connecting to A and D boards and now I am getting very faint lines across the top of the screen.
Doesn't this indicate and issue with SC and SU boards ?

[tom66]

Re: TH-46PZ85U no picture

No... SC only makes screen light up - never changes picture content apart from messing up brightness/pixel stability/image retention etc. etc.

SU maybe could be at fault but I would suspect more likely a D board issue.

Maybe try reseating even more cables and see where you get with that.

[dietzcj]

Re: TH-46PZ85U no picture

I already replaced that D board.
So you think it could be the SU board ?
The SU board according to the service manual controls the upper half of the screen.
I am still concerned that there is no video being produced.
But then again I am an amature.

Thanks tom66, you have helped me several times before. Just wanted to show my appriciation.

[tom66]

Re: TH-46PZ85U no picture

I would suggest SU then. You may be able to try without SU and get top of the screen to light up. Try jumpering SC50 if available, if set gives 7 blinks when doing attempting this.

[dietzcj]

Re: TH-46PZ85U no picture

Ok, how do I "jumper" that board ? Do you mean disconnect it and connect aligator plugs to a terminal ?
Or are there "jumper" switches ?
I am such a n00b.

Edit: I just unplugged the SU board and I do indeed get 7 blinky -blinks on the LED.

That probably means it is bad ?

[tom66]

Re: TH-46PZ85U no picture

No, it just means the TV detected the SU unplugged and doesn't like it. To disable the detection you need to locate the SC50 connection on the SC board. It should be a 2 pin header. Touch and hold a screwdriver across these pins and the TV should power up as if the SU is installed even if it isn't.

[dietzcj]

Re: TH-46PZ85U no picture

Okay, can you circle where this is, looking very hard.
Is the SC50 on the underside ?

[tom66]

Re: TH-46PZ85U no picture

Your set might not have it... I am checking the service manual give me a moment. It might be that other long connector - some combination of pins.

[dietzcj]

Re: TH-46PZ85U no picture

Is it this proceedure ?

[tom66]

Re: TH-46PZ85U no picture

Yes.



Training manual for your set (more in depth); on page 63.

[dietzcj]

Re: TH-46PZ85U no picture

With disconnecting the SU board (using the isolation method described in the maual) it does power on but the top half of the screen does not light up. (lower half is very dim just like before) No 7 blinks either.

Nor is there any video ( I would expect to see snow or setup menu in the lower half)

I assume that it means the SC / SD or SU are all bad ?

[tom66]

Re: TH-46PZ85U no picture

It is normal to get no light at all from disconnected half.

The other half may not show a video if there is no video input. Try entering the setup menu or similar, or perhaps try randomly switching inputs with a DVD attached.

[dietzcj]

Re: TH-46PZ85U no picture

I cannot see any menu at all, even the service menu.
There is no video at all.
could it be multiple cards affected ?
By the way we disconnected the SU board where there is no light at all.
As a test I un plugged the A5 plug from the A board. And the backlights came on and I could see that the SU board had black lines across the screen.
Plus this is making me think that the A board and the SU board are both bad.

[tom66]

Re: TH-46PZ85U no picture

There are no backlights in a plasma panel. You will get light emission when dark image is used due to the priming of the panel (necessary to make pixels light up.) Each pixel is self emissive. It generates its own light.

The fact that you are getting priming means the SC and probably the SU/SD are OK, as well as the SS. All are necessary for good priming to occur.

If this TV has a separate D board that's probably OK.

My bet would rest on the A board somehow or the composite "A" board which integrates D board functions.

[dietzcj]

Re: TH-46PZ85U no picture

Here is the photo of the tv in action with the A5 unplugged.

[tom66]

Re: TH-46PZ85U no picture

It looks like the D board is doing everything it can, the A board is just not sending it a signal.