Dell w4201c hd pdp hdtv plasma tv

[starmaxpc]

picked this item up yesterday from a guy who was gonna toss thought id give it a shot.

i press the power button on, blue light come on, it stays on, clicking in the power relay switch area, plasma does not light up.

no signs of bad caps, the area looks good. im not a pro tech and i don't have the electrical knowledge but if led i can follow well enough. it has to be something simple im hoping. looks to be a really nice tv.

any thoughts or ideas. i will post pics if requested but i just didnt want to load a bunch up at the time. just thought id ask first and show later. thanks.

[PlainBill]

Re: Dell w4201c hd pdp hdtv plasma tv

Post one picture of the back of the set (with the cover removed). That will help identify who made the plasma panel, and give us the information to request more detailed pictures.

Attach it using 'Manage Attachments' - below the text entry area.

[rayrod81]

Re: Dell w4201c hd pdp hdtv plasma tv

These are known for failures of two capacitors on the power supply. Most of the time they show no signs of failure. Coppell TV wrote an article about this problem here: http://blog.coppelltvrepair.com/2010...o-picture.html

Now, it is also possible that the Y-main and buffers could have failed as this TV uses the LJ92-01200A, -01202A, -01203A Y-main and buffers. If that is the case then it might not be worth repairing.

I would suggest checking voltages coming out of the power supply as your first step. First, check voltages with all boards plugged in. If you do not get correct values then disconnect the Y-main and recheck. Reconnect the Y-main and disconnect the X-main and recheck. Finally disconnect both and recheck if you still do not get correct voltages then the power supply is the problem. At that point I would suggest replacing the two caps mentioned in the above article as they are responsible for the Vs-On signal from thr main board.

[starmaxpc]

Re: Dell w4201c hd pdp hdtv plasma tv

AWESOME thank you so much!! i will dig into this and post back!!

[starmaxpc]

Re: Dell w4201c hd pdp hdtv plasma tv

a couple pics attached little blurry sorry as i wasnt able to lay this monster down for a good top view photo. it is pretty heavy!!

[PlainBill]

Re: Dell w4201c hd pdp hdtv plasma tv

a couple pics attached little blurry sorry as i wasnt able to lay this monster down for a good top view photo. it is pretty heavy!!

Note Rayrod's advice on the Y-sustain and the Y buffers. If these are shorted, consider the TV unrepairable.

PlainBill

[starmaxpc]

Re: Dell w4201c hd pdp hdtv plasma tv

As i do not have the electronic experience with this type of repair i may be in a lot over my head so please bare with me....to just go ahead and test for shorts i wouldn't know where to start so i just did some cable plugging / unplugging and here is what i found. hopefully this may help.

there is a small green light on the main panel at the bottom just right of the PHILIPS cable output when power cable is plugged in.

everything plugged in normal i press the power button and i hear 3 clicks coming from the power relay boxes. when i press the power button off. no clicking sound.

with only the x-main unplugged i hear 2 clicks but when powered off i hear one click.

with only the y-main unplugged i hear 3 clicks but when powered off no click.

i hope this may narrow it down as like i said this may be beyond my capabilities to properly test the unit. thanks.

[PlainBill]

Re: Dell w4201c hd pdp hdtv plasma tv

As i do not have the electronic experience with this type of repair i may be in a lot over my head so please bare with me....to just go ahead and test for shorts i wouldn't know where to start so i just did some cable plugging / unplugging and here is what i found. hopefully this may help.

there is a small green light on the main panel at the bottom just right of the PHILIPS cable output when power cable is plugged in.

everything plugged in normal i press the power button and i hear 3 clicks coming from the power relay boxes. when i press the power button off. no clicking sound.

with only the x-main unplugged i hear 2 clicks but when powered off i hear one click.

with only the y-main unplugged i hear 3 clicks but when powered off no click.

i hope this may narrow it down as like i said this may be beyond my capabilities to properly test the unit. thanks.

That sounds like the Y-sustain - Y-Buffers problem. Read the following blog entries from Coppell TV.

http://blog.coppelltvrepair.com/2010_03_01_archive.html

http://blog.coppelltvrepair.com/2010_06_01_archive.html

http://blog.coppelltvrepair.com/2010_10_01_archive.html

PlainBill

[jayoung]

Re: Dell w4201c hd pdp hdtv plasma tv

I was given a Dell 4201C HD plasma TV from the local computer store that does electronics recycling. I have read through several posts on badcaps.net and also the articles on coppelltvrepair.com. I ordered the two capacitors from digikey.com (p/n 493-1501-ND) and replaced them tonight. The only sign of life is still the blue LED and I get no picture and no sound. I tried powering on with everything plugged in, with the z-sustain unplugged, with the z-sustain and y-sustain unplugged, and with the z-sustain, y-sustain, and control board unplugged with no change in function.

Voltages with everything plugged in: (label - specified on label - actual)
Va - 70 Vdc - 70.3 Vdc
Vs - 207 Vdc - 209 Vdc
Vsc - 190 Vdc - 191 Vdc
Ve - 84 Vdc - 84.2 Vdc
Vset - 190 Vdc - 191.1 Vdc

From my reading, it would appear this TV is destined to head back for recycling. I just wanted to get a second opinion before taking it back.

Thanks in advance.

[jayoung]

Re: Dell w4201c hd pdp hdtv plasma tv

anyone?

[tom66]

Re: Dell w4201c hd pdp hdtv plasma tv

Did you check the other voltages, such as 5V, from the power supply?

[jayoung]

Re: Dell w4201c hd pdp hdtv plasma tv

12V - 12.03 Vdc
5V - 5.22 Vdc

[nativenerdpatrol]

Re: Dell w4201c hd pdp hdtv plasma tv

I am working on a similar plasma TV, a Dell w5001c hd, with similar problems no video or audio but the blue power light comes on and the relay clicks. I read the Coppell article about the bad caps and I noticed the w4201c is almost the same tv with the same design defects. So today googled Dell w4201c to see what comes up and found this website. I also found plasmafix.com and they have troubleshooting tips and a list of repairs for TVs they have fixed by model number. The w4201c is listed that powers on but no picture, and it was a shorted buffer board and Y sus board.

This is the same thing I found after I replaced the bad caps mentioned on the Coppell website and still had no video. I checked the voltages on the PS and they were like yours close to the specs. Then I found an instructables.com repair article http://www.instructables.com/id/Dell...ot-plasma-fix/ where I learned about other known problem areas in Samsung plasma TVs including the buffers. So I followed the instructions from Coppell on how to check the buffers with an Ohm meter. They also mentioned that if one blows it takes the rest with it. Both of mine were blown (LJ92-01277A and LJ92-01276A) so I looked at the Y sus board (LJ92-01275A) and found 4 shorted SMD zener diodes near the upper buffer socket (ZD5024, ZD5023, ZD5017, ZD5016). I googled the part number RLZ33B but I could not find a replacement. This board is hard to repair because there are no service manuals or parts list available. Also plasmafix.com does not mention the location of the bad mosfet.

So I decided to replace the Y sus board and both buffers. Shopjimmy.com had the cheapest price for the buffers with a six month warranty but did not have the Y board. The cheapest place I found was tristatemodule.com with a 6 month warranty. In total it will cost about $250 in parts to fix the TV and that is cheaper then any 50 inch out there. Youtube also has a lot of good fix it videos and that is how I located the zeners on the y sus board.

[PlainBill]

Re: Dell w4201c hd pdp hdtv plasma tv

Thanks for the links. Always glad to have more sources for information.

PlainBill

[genienabottle]

Re: Dell w4201c hd pdp hdtv plasma tv

I found this one by the recycle bin in my neighborhood so I took it home to give it some love. expecting the worst... Well it powered on fine and I connected it to a dvd player the picture was crystal clear sound was ok but the right speaker's sound was fluctuating up and down periodically thorughout the movie. I left home and came back 2 hours later and now It powers on (blue light) but no picture. I knew it was to good to be true. well any way I am curious to know if it is fixable??????? and how would I replace the bad caps if there are any?

[tom66]

Re: Dell w4201c hd pdp hdtv plasma tv

You can start by taking pictures and we can highlight the failed caps.

[Peter Chiu]

Re: Dell w4201c hd pdp hdtv plasma tv

4 shorted SMD zener diodes near the upper buffer socket (ZD5024, ZD5023, ZD5017, ZD5016) . those are 5.1v Zener, unsolder them (protection only)
. and I just fix this dell 50" TV.

[Freakyfabe]

Re: Dell w4201c hd pdp hdtv plasma tv

I know this is an out dated thread, but what does the post above mean??? Did he just remove those diodes????

[CoppellTVRepair]

Re: Dell w4201c hd pdp hdtv plasma tv

4 shorted SMD zener diodes near the upper buffer socket (ZD5024, ZD5023, ZD5017, ZD5016) . those are 5.1v Zener, unsolder them (protection only)
. and I just fix this dell 50" TV.

Just read that and I can't say I agree with it.

4 zener diodes in a row @ 5.1V each make zener of 20V.

They are on the sustain output where voltage is easily Vs at peak, i.e. over 100.

Have you actually tried putting 5V zeners there?

because I think they'll fry right away.

[shelby5041]

Re: Dell w4201c hd pdp hdtv plasma tv

i know this thread is years old but i just got a dell w4201cHD from a guy for $10..he said it wouldnt power on..but panel would not come on

well i bought it for the heck of it yesterday and tinkered with it today and here is what i have found so far

apparently it uses same buffers and y as my philips 42 plasma i worked on years ago and i kept some parts from that tv that were giving issues but tv would power on

anyways..the dell would have a blue light on front but the panel would not come on...i noticed the upper and lower buffers were replaced at one time...tv was made in 2005 and had 2008 buffer boards in it...i disconnected the y and z and tested power supply and seem to get vs 235v va 70v and 5v standby...and it appeared it has 2 new caps on it that are common failures on ps...so i believe ps is good...so i moved onto testing the buffers and y

per coppell tv procedure the buffers tested shorted.....so i removed the heat sinks and yes there were a couple burnt ics on each board....i then went to do some testing on y board...the y board main fuse was good...the ic did not test shorted....i checked all the small pico fuses and all were good except 1 @ F5006 which was open...

so i figured the buffers were both bad and the y was bad....so i looked in my box with old phlips parts and found an upper and lower buffer that gave pink lines and grainy...and i found a y that gave grainy pic....both were exact same part numbers as the dell..they both use samsung panel

i then installed these for the hell of it in the dell and the tv powered on and the panel immediatley came on....but pic was grainy and messed up bad...real funky looking

but thats a good sign...tv now powers up so power supply is good and im pretty sure new buffers and y will fix this tv..

only problem is the parts are costly...ill try to find them cheap..if not then i will sell ps and stand and make a few $$