Pioneer PDP-LX5090 powers off straight away.

[Dang]

Hi all, one for Tom maybe but of course open to all ideas, I've just got it today for £40, it was said to have a 3 red standby light flashing error(from my research possibly a scan IC or Y-sus error), I haven't as yet seen this as I've only powered it up once as I don't want to risk anything breaking further, when I did this there were two clicks in quick succession and she fired up briefly, it looks like the EXT box came up all brightly lit and then it powered off, I didn't see any flashing standby light. This is where I left it hoping that you guys could help in understanding what the fault might be, I know how to use a basic DMM and know that I could disconnect certain boards to see if any are at fault causing a short but being this Pioneer plasma, and of this potential worth I'm a little reluctant in case I break something or something blows in the process.

I will take some pictures, just waiting for the battery to charge but all looks OK to the naked eye, the scan ICs look OK, nothing obvious with the Y-sus and the X-sus looks fine too. So all I need is a place to start, I'm going to start checking as many components as I can whilst it's off and I'll post my findings in due course, thanks.

[Andrew F. Ali]

Re: Pioneer PDP-LX5090 powers off straight away.

First self-test the Power board. then go from there. Some pics would of great help.

[Dang]

Re: Pioneer PDP-LX5090 powers off straight away.

First self-test the Power board. then go from there. Some pics would of great help.

Hi and thanks for help, not too sure on how to do that, I guess I need to disconnect both the Y-sus and X-sus?

[zomi]

Re: Pioneer PDP-LX5090 powers off straight away.

do not power on with the back off
you will acitvate the tamper function.

[zomi]

Re: Pioneer PDP-LX5090 powers off straight away.

service manual attached

[Dang]

Re: Pioneer PDP-LX5090 powers off straight away.

do not power on with the back off
you will acitvate the tamper function.

Yep, read somewhere something about that, how does the Tv know? a switch somewhere?

[Dang]

Re: Pioneer PDP-LX5090 powers off straight away.

Just seen this: https://www.youtube.com/watch?v=dFZV0TADHBU, seems it will help if needed.

[Dang]

Re: Pioneer PDP-LX5090 powers off straight away.

Just to add, I can't find this switch or anything like it with this Tv, any ideas where it might be if indeed it has one?

[Dang]

Re: Pioneer PDP-LX5090 powers off straight away.

service manual attached

Thanks by the way, I'm sure it will be a big help.

[Dang]

Re: Pioneer PDP-LX5090 powers off straight away.

Hi again, I need some pointers please or some experience of this error, I've read the service manual but being just a hobbyist it's a little hard to know where to start, is there anything specific I could test?, is there an anti-tamper device and if so where? could the X-sus be at fault? I would love to power it up with back off but this anti-tamper idea is killing my progression, Tom66, any ideas? you've had issues with one of these and I believe you still have it?? thanks in advance.

[tom66]

Re: Pioneer PDP-LX5090 powers off straight away.

What does the error code for 3 red say?
These sets do NOT use the tamper switch and are safe to run with the back cover off.
You can try isolating X and Y drive and see if the error codes change.

[Dang]

Re: Pioneer PDP-LX5090 powers off straight away.

What does the error code for 3 red say?
These sets do NOT use the tamper switch and are safe to run with the back cover off.
You can try isolating X and Y drive and see if the error codes change.

Thank you, it says either a scan issue or sustain, I've checked the scan ICs visually and they all look perfectly fine, nothing obviously blown and I've checked all the components I can while in-situ of both the Y-sus and X-sus, all seem fine, I've also checked a few from the PSU. Now that I don't have to worry about this tamper switch I can turn the thing on and do some proper checking so I'll get back on here and let you know my findings, thanks.

[Dang]

Re: Pioneer PDP-LX5090 powers off straight away.

Hi again, as of yet I've not tested any voltages as the set tries to turn on but I have disconnected the power from both the Y-sus and X-sus boards and I'm still getting the three red flashes followed by a pause(slightly strange as the service manual says a possible scan IC fault or a sustain issue), seen as it's only the logic board and mains connection board still connected, I'm guessing there's a power fault with the PSU, I shall look a little further later but any ideas on this would be useful? thanks, Andy.

[tom66]

Re: Pioneer PDP-LX5090 powers off straight away.

If you suspect a PSU issue check the Vsus and Vadr voltages. They are similar to Vs/Va (although Vadr is around 75-80V)

Personally I'd look at Y drive. Many voltages produced by this board, including but not limited to:
- Vh (~130-150V above floating gnd)
- Vknosfad1,3,4
- Vprst
- Voffset
- Verc (1/2 Vsus)

The multiple different voltages bias the panel into displaying a very high contrast image. They are different for each panel, values written on panel sticker. Note values written in range 0-255, these are programming values and the actual voltages can be determined by using the formula in the service manual.

[Dang]

Re: Pioneer PDP-LX5090 powers off straight away.

So I've removed the PSU and as far as I'm concerned all components measure out fine using the diode setting, nothing blown or obvious so it's voltages tomorrow(I would do it sooner but kids around off school, out tomorrow).

[tom66]

Re: Pioneer PDP-LX5090 powers off straight away.

No point searching for something broken if you don't know if the part is broken in the first place.

Narrow it down, the first step in virtually any repair is to test voltages and observe system behaviour.

[Dang]

Re: Pioneer PDP-LX5090 powers off straight away.

No point searching for something broken if you don't know if the part is broken in the first place.

Narrow it down, the first step in virtually any repair is to test voltages and observe system behaviour.

I do agree with you but I have had good success in using this method in the past, one thing I do still find a little strange is that I've disconnected both the Y-sus and X-sus from the power supply yet I still see the same error code, it's supposed to be a scan IC or sustain issue, if they're out of the equation why is the Tv still acting the same way?

[tom66]

Re: Pioneer PDP-LX5090 powers off straight away.

Because these sets will detect missing boards and connectors and fire errors if they detect anything wrong there. They are closer to Panasonic than a Samsung or LG, except they have many more possible error states and detection logic.

Seriously, just test voltages. It ain't difficult. That'll get you going in the right direction.

[Dang]

Re: Pioneer PDP-LX5090 powers off straight away.

Because these sets will detect missing boards and connectors and fire errors if they detect anything wrong there. They are closer to Panasonic than a Samsung or LG, except they have many more possible error states and detection logic.

Seriously, just test voltages. It ain't difficult. That'll get you going in the right direction.

OK, thanks, at some point I'll get to it this weekend, Andy.

[Dang]

Re: Pioneer PDP-LX5090 powers off straight away.

OK, so after some close looking, taking voltages etc I've found a blown chip on a board, second right at the top along the screen, Z-board I think, I guess it can be carefully removed and replaced but not too sure why it might of blown, any ideas?

I'll get a photo or two done in a moment.