Pioneer Plasma TV on standby and won't power on

[romanator]

Hello, looks like there are some smart / experienced folks on here so thought I'd ask for help in trying to fix a tv.

My Background: noob/enthusiast when it comes to fixing electronics, pro when it comes to using them . I'm very mechanichaly inclined though just need to know what to do.

Story: saw a plasma at goodwill, looked good, red standby light was on but tv didn't power on, 30 bucks, figured it was worth getting and seeing if I could get lucky. Plus I used to have a pioneer elite projection tv, that had power supply issues (ended up just being bad connections on power supply board from heating and cooling, made it work).

TV: Pioneer Plasma PDP427CMX

Issue: won't power on when pressing power button, standby red LED on front of tv stays on, solid red when tv plugged in and power switch is turned on.

Goal: to make this TV work, hoping that it's something simple and not a few boards that actually need replacing at a few hundred bucks a piece, would be sad to throw away such a nice piece

What I've done so far:
-took back of plasma off
-researched what could be wrong when similar issues
-results came back as bad power supply board or caps
-looked around all boards and caps and everything looks good
-also noticed a red LED on power supply board that is not on and a tiny red LED on a small board next to power supply board that is on, so small that i wouldn't notice it was an LED if it wasn't on (not sure if these are supposed to be on or off but wanted to say in case it means anything).
-checked connections on boards, all look good
-researched more about caps
-noticed two caps on power supply board (near them the part of the board was labeled "secondary") could possibly be bad, were just slightly bloated on top, ordered same 2 caps on mouser (250V 820uF), removed old ones, soldered on new ones, plugged in TV, power switch on, crossed my fingers, pressed power.... nothing changed .

Not too surprised since i troubleshoot stuff all the time and usually first thing usually doesn't fix the issue, would be nice though .

So now I'm here because I don't give up that easy and hoping that maybe someone can give me some input on what/how to check or maybe someone here has worked on one of these TV's.

Tried to be as descriptive as I could but if I missed something please let me know, also can post pics later tonight if they might help.

Thanks for reading and look forward to any asistance on the matter so i can press that power button and smile when that red standby light turns to green!

[tom66]

Re: Pioneer Plasma TV on standby and won't power on

Be careful with these sets. They have a light sensor which locks them out (I kid you not) if you try to power them up with the cover removed. There IS a way to reset it but it's a pain in the behind and requires the original remote.

Sienoki knows a lot about these, he fixed a similar 43", apparently the media box was at fault.

[romanator]

Re: Pioneer Plasma TV on standby and won't power on

Thanks for your reply tom66.
Yikes! tried powering up with the cover off, so maybe I am locked out, I don't know how to tell, that's crazy. I also don't have the remote. But maybe the lockout feature only works if the tv is functioning properly?
Media box? like dvd/direct tv box/ps3? I don't have the TV hooked up to anything, it should still power on at least without anything hooked up right?

[Mt.Man]

Re: Pioneer Plasma TV on standby and won't power on

Tom66, JVC uses the light sensor. Pioneer uses the trap switch that the back cover keeps pushed in. Just tape down the switch before connecting to AC.

This TV is G7 series. Trap indication is the Red & Blue LED's are on. TV is in lock down mode.

To reset:
• Using the customer’s remote control enter “service mode” by pressing the
following key sequence:
1. Press and release the “display” button.
2. Wait between 3 and 10 seconds
3. Press and release the “<”, “^”, “<”, “>”, and “power” buttons in sequence.
• Panel will now turn on in “service mode”.
4. Press “muting” button 3, 4 or 5 times depending on model you are working on.
Or until display shows the “initialize” page.
5. Press and hold the “display” button until the error indicator (red LED) on
either the panel or the media receiver goes out.
6. Exit service mode by pressing the “power” button on the remote.

If your in just constant Red LED on front panel, that standby mode. Pressing power on the remote you should hear relays clicking on the power board. If nothing you may have a bad main board. Usually when the TV fires up and detects an error your Red and Blue LED's will give you a blink error code.

[sienoki]

Re: Pioneer Plasma TV on standby and won't power on

Thanks for your reply tom66.
Yikes! tried powering up with the cover off, so maybe I am locked out, I don't know how to tell, that's crazy. I also don't have the remote. But maybe the lockout feature only works if the tv is functioning properly?
Media box? like dvd/direct tv box/ps3? I don't have the TV hooked up to anything, it should still power on at least without anything hooked up right?

Hey up fella..im not sure if your tv needs a media receiver box inorder for your tv 2 work..from a little research it seems you dont..so if you take pictures of your insides of the plasma im sure sum1 will point u in the right direction

[romanator]

Re: Pioneer Plasma TV on standby and won't power on

LED in front of set doesn't blink, stays constant red. I don't have the remote, when I press the power button, nothing happens exept the one little red LED on a small board between the power board and the main board turns on and also stays constant red (don't know if there's any significance to this little light), no clicking no buzzing, no humming, fans don't turn on.

I'll take some pictures this evening and post them in case that helps solve anything. Thanks for the replies guys, appreciate any input to lead me in the right direction.

[romanator]

Re: Pioneer Plasma TV on standby and won't power on

here are a pics of the back panel and power supply, any way for me to check if the power supply is working properly? I have a multimeter. Thanks

[romanator]

Re: Pioneer Plasma TV on standby and won't power on

any ideas guys? What would you check?
Thanks,

[tom66]

Re: Pioneer Plasma TV on standby and won't power on

Once that small LED on the board is on, does pressing the power button again turn it off?

[romanator]

Re: Pioneer Plasma TV on standby and won't power on

nope, doesn't seem to do anything

[tom66]

Re: Pioneer Plasma TV on standby and won't power on

That generally points to either:
a) locked out (have you tried above method for unlocking?)
b) other mainboard problem

As you have power but main board is going no further once turned on.

[romanator]

Re: Pioneer Plasma TV on standby and won't power on

I don't have the blue light on, just the red, I'll try it tonight with my universal remote since I don't have the original.. or I wonder if the sequeence can be entered using the buttons on the TV, I'll find out.

[tom66]

Re: Pioneer Plasma TV on standby and won't power on

You need to use the original remote or one which has all of the functions available. Since the TV doesn't work you can't confirm that but it's worth a shot...

[betta]

Re: Pioneer Plasma TV on standby and won't power on

Hi, I have what seems to be exactly the same problem with a pioneer PDP 42MXE10: Red light in standby and it does not turn on. The pictures that you posted look exactly as the inside of my monitor. Did you have any success in fixing the problem? Did you try to check the integrity of the voltage at the outputs of the power supply board using a multimeter?

[cadiman]

Re: Pioneer Plasma TV on standby and won't power on

This set should have red and blue leds that will both be lit if powered on with cover removed. (lock out)

I am not sure if all cmx models have both leds or not.

The main problem with these sets is buffer chip failure. The bigger problem is the buffer ics are part of the plasma panel and need to be replaced while still attached to the panel as there are no connectors from the panel to the buffer boards.

[irep]

Re: Pioneer Plasma TV on standby and won't power on

But if it was it should lit 3 times.

Still pointing to Power source problem. and also check cables connections to boards.

Also check atservice manual the output voltages in standby mode.

[freakaftr8]

Re: Pioneer Plasma TV on standby and won't power on

Are you trying to power up the set with the switch on the bottom of the tv? That switch only kills the standby. Some pioneers like tom66 said require the remote control to power it up only.

[kokomoto]

Re: Pioneer Plasma TV on standby and won't power on

I just bought a used Pioneer TV, model PDP-5070HD and all was working well until today. It went on Standby mode, and I couldn't get the power to turn on. I unplugged it, waited a bit, plugged it in, but still couldn't turn it on. I am not a technie or a mechie, but after trying a bunch of things, I thought over what I had done earlier in the day . . . I had hooked my PC up to the TV, chosen PC input, and changed my display so it would show on the TV. I had watched TV for a while, then walked away. I think the TV went into Standby mode because my PC would have gone to sleep, thus making the TV go into Standby mode after a while. That was the only different thing I had done today. So my "fix": with the TV in Standby mode, I pushed the "PC" input button and fiddled around with computer display settings, and I may have punched a few other buttons, but basically I put the TV back in the mode before it went to sleep, and then I managed to get the power back on. I wonder if some of these problems around not being able to get the TV out of Standby mode is simply that the input is wrong combined with the wrong display setting. Once I got the TV on, I checked my Power settings to turn off Standby, but Standby had already been disabled, so in future when I'm using my TV to watch something on my PC, I will make sure I put the input back to the HDMI input for my cable converter. I have since turned my TV off and on without problem.

[dabbott231]

Re: Pioneer Plasma TV on standby and won't power on

Tom66, JVC uses the light sensor. Pioneer uses the trap switch that the back cover keeps pushed in. Just tape down the switch before connecting to AC.

This TV is G7 series. Trap indication is the Red & Blue LED's are on. TV is in lock down mode.

To reset:
• Using the customer’s remote control enter “service mode” by pressing the
following key sequence:
1. Press and release the “display” button.
2. Wait between 3 and 10 seconds
3. Press and release the “<”, “^”, “<”, “>”, and “power” buttons in sequence.
• Panel will now turn on in “service mode”.
4. Press “muting” button 3, 4 or 5 times depending on model you are working on.
Or until display shows the “initialize” page.
5. Press and hold the “display” button until the error indicator (red LED) on
either the panel or the media receiver goes out.
6. Exit service mode by pressing the “power” button on the remote.

If your in just constant Red LED on front panel, that standby mode. Pressing power on the remote you should hear relays clicking on the power board. If nothing you may have a bad main board. Usually when the TV fires up and detects an error your Red and Blue LED's will give you a blink error code.

Will this work with Pioneer PDP5072HD?

[splitcrete]

Re: Pioneer Plasma TV on standby and won't power on

Is the lock out switch, normally open or normally closed. I would disable that bad boy first