Quirky 42" Phillips Plasma TV (42PF9631D-37)

[FlyingHigh85]

Re: Quirky 42" Phillips Plasma TV (42PF9631D-37)

The TV turned-on again today...and has been on for ~6-hrs. I think I've figured out the problem. This time while I was powering it on, I was insulting it. Maybe it just needs to be knocked down a peg or two from time-to-time. I haven't tried hitting it yet, but I think there is a line and physical violence would be crossing it.

Yesterday, while the TV was throwing the 6-3 code, I tried to disconnect the audio board as you suggested, capkid. Sorry I didn't mention it before. It didn't seem to do anything. The TV still gave me the 6-3 error code. No video. Thank you for the suggestion, though.

I scanned the PSU board while I had it out of the TV twice with a flashlight. Like I said, I have an untrained eye, but I didn't see any obvious shorts, damaged traces, or faulty components. On a side note, can anyone tell me what the "clicking" noise is I hear coming from the PSU when I initially plug-in and power-on the TV? There's usually one click when I initially plug it in, and one click when I hit the "power" button. *Edit: so the clicking is likely a relay and indicative of one or more faulty caps.*

I'm part-way through tom66's "A guide to fixing/troubleshooting some common plasma TV problems." While the TV was throwing the 6-3 error code yesterday, I tried unplugging the z-sus and y-sus (or at least what I think are the z-sus and y-sus) as suggested with no positive results, no video or audio, just the 6-3 error code. When I next power-off the tv and it gives the 6-3 code again, I will try to unplug the upper and lower buffers, if I can figure out where they are located...

I will also check the fuses on the PSU (there are four, I believe) with a DMM when it is next powered-off.

I tried plugging the TV in this morning before I went out to run errands for a few hours. It only gave me the 6-3 error code. No audio/video. When I came back, I plugged the TV in and it powered-on. It took ~10-seconds to get video. The TV has been on ~6-hours now and the PQ doesn't seem to have degraded. No led flashes. The led (printed "LED8001") on the PSU board is on steadily.

I tried touching the larger capacitors on the PSU while the TV is on (which, I'm sure, is a smart idea) and none of them are warm to the touch.

I've tried to adjust the video (saturation, color, color temp, brightness, tint) because the reds seem to be much more red than the blues are blue. When I turn-up the saturation, color, and color temp, the blues increase, but so do the reds. Is there some way to increase blues (cooler temp colors) without increasing reds (warmer temp colors) as well? I've included pictures of a LED display vs. the plasma display in question. I was using a point-and-shoot camera for the plasma, but I think I captured the PQ pretty closely to what I see in real-life. The LED display (first pic) is ~1-yr-old and the plasma display is ~7-yrs-old.

[FlyingHigh85]

Re: Quirky 42" Phillips Plasma TV (42PF9631D-37)

Since I don't see any obviously bad caps and one or more bad caps on the psu is likely...should I desolder as many caps from the psu as I can and test them with a capacitance meter. Or maybe remove one-half of the capacitors and test with esr meter? I wish there was an easy way to test caps while in circuit.

TV has been on now for ~8-hrs. The heatsinks on the psu must be near 95C, but the caps seem only warm to the touch (~40C). This TV throws-off A LOT of waste heat, albeit I have the brightness at ~90%. I've disconnected the source (a dvd player), but haven't turned-off the tv. I left the house for ~half-hour and the dvd I was playing ended and went to the dvd's menu screen. Now that I've disconnected the dvd player, the screen is dark for the most part, but glowing slightly and I notice some IR due to the dvd menu screen being on for ~30-min.

I wonder how much power this display uses when turned on, but with no source (a dark screen that is only glowing very slightly). *Edit: It seems the tv powers-off if no source is detected. I tried to power it back on, but now have no video. There is audio, and the LED on the front of the tv and on the psu is on steadily. Cycled power to the tv one more time...there was audio, no video, for ~5-seconds, then audio cut-off and the led began the 6-3 flashing again.*

Can't edit previous post, too much time elapsed...

[freakaftr8]

Re: Quirky 42" Phillips Plasma TV (42PF9631D-37)

those small boards that are standing up on the power supply. Hit them with freeze spray with the TV doesn't want to turn on and then see if powers up

[FlyingHigh85]

Re: Quirky 42" Phillips Plasma TV (42PF9631D-37)

Update:
Now the TV's audio consistently turns-on, but before the video turns-on, a relay on the psu board clicks once. Then the audio cuts-off and the led on the front of the tv flashes 6x(slow)3x(fast). The led on the psu board is also illuminated. I read elsewhere that this is indicative of a problem detected on the psu board.

I bought a DMM and checked some voltages. There is a sticker on the PDP with a list of recommended voltages: Va=65V, Vsc=-185V, Ve=110V, Vs=197V, Vset=195V. The readings that I saw with my DMM are: Vscan=290mV, Vset=-5mV. As for the Vs, Ve, and Va, these all build to 9V, then a relay on the power supply board clicks once and all these voltages drop to zero over a period of 30-seconds.

I used the DMM to check all the fuses (including 4 on the psu board) and all checked OK. My next step is to try to find some freeze spray to use on the boards attached vertically to the psu board.

I tried disconnecting the audio board, x-main, and y-main one at a time and saw no change. This leaves me to believe the problem is somewhere on the psu board.

[FlyingHigh85]

Re: Quirky 42" Phillips Plasma TV (42PF9631D-37)

I found a few hours to work on the TV over the holidays. I replaced eight of the larger capacitance capacitors (2x 1500microF 10V, 6x 2200microF 16V) on the PSU with new Rubycon and Nichicon capacitors from Digikey. The TV now powers-on and works normally about every three out of five attempts. The other two times out of five I try to power-on the TV and it still has the same problem: it does not power-on and the LED on the front of the TV blinks a 6-3 pattern.

I still don't know what the problem is, but this is a step in the right direction. Before I replaced the capacitors, the TV would only power-on properly in something like one out of fifty attempts. Another bit of good news: I successfully replaced capacitors on a PCB for the first time!!!

After using the TV in question for the past few days, I'm not sure I want to invest anymore time in it. The picture quality of the plasma is pretty good compared to most of the LED TVs I have seen in stores (even though it is a 7-year-old 720p plasma), but this thing runs hot. VERY HOT! Since I live in Florida, USA, I'm thinking I would rather invest in a cooler-running LED TV. Then there is the question of power consumption. I saw somewhere that an LED TV uses something like 1/2 to 1/4 the power of a similarly sized plasma TV.