PDP-4304 solid red/green LEDs

[brainiac88]

Hi all,

I have a Pioneer PDP-4304. It refused to turn on, so I did some initial troubleshooting a few months ago, and decided to replace the power supply. I installed the new power supply but did not know about this diabolical trap switch. So I turned it on and of course, it did not power up. Instead, I have solid red and green LEDs on the front. I also research as best I could on how to reset this trap switch through the remote, but that did not work either. Couple possibilities:
1 - Something else was broken, not the power supply
2 - The trap switch reset method I used was incorrect / ineffective
3 - ???

I verified that the remote does emit IR light by looking at the emitter using my phone's camera.

Any ideas would be greatly appreciated.

[brainiac88]

Re: PDP-4304 solid red/green LEDs

Bump..

Anyone?

Help, please?

[nuala]

Re: PDP-4304 solid red/green LEDs

Do you get any blinking code from the led after turning the set on.

[brainiac88]

Re: PDP-4304 solid red/green LEDs

No blinking, just aolid red and solid green front LEDs...

[R_J]

Re: PDP-4304 solid red/green LEDs

Trap Switch Reset Procedure
G-4, G-5, G-6, G-7, G-8
• Replace media receiver, plasma panel cover, or tape down HDCP trap switch.
If the model in question has the TV Guide option, the TV Guide
option must be turned off before proceeding.
• Using the customer’s remote control enter “service mode” by pressing the
following key sequence:
1. Press the “display” button then release the “display” button.
2. Wait between 3 and 7 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.
Until the 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 a circuit failure will not permit the unit to remain powered-on long
enough to complete the above procedure, clear the Trap Switch as follows:
(You will not be able to see the menus.)
1. Turn off Main Power Switch on Panel or unplug panel.
• Depending on which model you are working on, place switch on Digital
Assembly from "Normal" to "Off" or use a clip to short the high
voltage. Shorting connections located on upper right corner of
digital video board. (preventing high voltages from activating)
2. Place Main Power back on.
• Confirm both Media Receiver and Panel are in standby mode (unit that is
trapped will still have both red and green LEDs lit)
3. Press the “display” button then release the “display” button.
• Wait between 3 and 7 seconds
4. Press and release the “<”, “^”, “<”, “>”, and “power” buttons in sequence.
• Listen to panel carefully. There will be a very slight relay click.
Panel will now turn on in “service mode” with only the low
voltage supplies operating. (no picture)
5. Press “muting” button 3, 4, or 5 times depending on the model you are
working on.
6. Press and hold the “display” button until the error indicator (red LED) on
either the panel or the media receiver goes out.
7. Turn soft power off, then main power off or unplug unit.
• Wait 20 seconds
8. Return switch on Digital Assembly to Normal position or remove shorting clip.
9. Power back on and troubleshoot normally.
TRAP SWITCH RESET FOR G-3
Press and release “menu,enter,power” in sequence or “enter,display,power”
Exit service mode by turning off power.

[brainiac88]

Re: PDP-4304 solid red/green LEDs

I carefully followed the procedure, and nothing happened. The TV did not turn on as stated in step 3 (after pressing “<”, “^”, “<”, “>”, and “power” buttons in sequence.)

Any other ideas?

[mmartell]

Re: PDP-4304 solid red/green LEDs

There is a knack to getting the timing down. Hard enough with a functional display never mind without it. I can be a little more concise by telling you what worked for me.

Press and hold the Display button for about a second then release it. When you release it begin to count "one-thousand ONE one-thousand TWO"... begin pressing the remainder of the sequence at FIVE once per second so that the Power button is pushed at NINE. Good luck.

[brainiac88]

Re: PDP-4304 solid red/green LEDs

I tried very patiently, multiple times, following the one-second cadence, without success. Where is the IR sensor on the TV anyway?

But I'm afraid the power supply I replaced isn't the damaged component. I don't know what to do next...

[brainiac88]

Re: PDP-4304 solid red/green LEDs

PROGRESS!!!

Okay so this is what I did:

0. With new AA batteries, point the remote at the lower right corner of the TV
1. Press the “display” button for 1 second, then release the “display” button
2. Wait between 7 and 9 seconds
3. Press and release the “<”, “^”, “<”, “>”, and “power” buttons in sequence

I head a click-click, then a faint buzz sound increasing in amplitude but still no picture or any illumination on screen.... then click. No more buzzing. Both front LEDs still solid.

I power-cycled the TV, then tried the sequence again. Same results.

Next, I will try the second part of the procedure mentioned above "If a circuit failure will not permit the unit to remain powered-on..." but that requires opening up the TV again... That's for another day.

[brainiac88]

Re: PDP-4304 solid red/green LEDs

More progress:

I read the Service Manual on Scribd and it mentioned the switch on the board beside the power supply. So I switched it to the UP position, and performed the procedure above, several times, changing the switch position, power-cycling in between, and trying 3,4, and 5 presses of the Muting button. After 20 minutes of trying, I finally cleared the trap indicator - only the red LED was lit. Yes, I taped down the trap switch.

So turning on the TV results in it shutting off after 5-10 seconds, and getting a twice-flashing red LED, which means a "power" fault, according to the Service Manual. I tried both power supply boards I have, and same result.

I guess now it's time to get another power supply board...

[brainiac88]

Re: PDP-4304 solid red/green LEDs

Replacement power board installed, but a used item from eBay. This one is also defective - twice flashing red LED.

[brainiac88]

Re: PDP-4304 solid red/green LEDs

More info: If I flip the switch beside the Power Supply board, the TV powers up and does not shut off. But when the switch is off, that means some circuits are not activated.

But when the switch is in the normal position, TV shuts off after turning on, then I get the twice flashing front red LED, and the red LED on the power supply board is lit.