Polaroid 3211-TLXB Cap Issue

[Ifixthings]

Hello all.
My wife was watching tv and the screen went black. After unpluging the TV then plugging it back in the pic came back for a min then lines went through the picture then the screen was still visible but white. I opened the TV and spotted a bad filter cap in the PS, which I hope is my only problem. I also read the troubleshooting guide and see bad T-con board with white screen. Hopefully that's not my problem.

Questions are can I get away with just replacing the 150uf 450v 105c Cap?
Or do I need to replace others that are known to fail? All others APPEAR to be in good condition, BUT I also saw a post here saying HEC caps under the heatsink could be iffy.

I tried to order a Panasonic cap from digikey and there are a TON of options/models. How do I know what series to buy ? Ripple current? Impedence?

I attached a picture of the PS b/c maybe somebody will recognize it from another polaroid model and can chime in.

thanks in advance

[R_J]

Re: Polaroid 3211-TLXB Cap Issue

That cap. is most likely o.k. it usually just the plastic that is bulged from heat. If that cap was bad chances are the tv would not work at all. I would look elsewere for the fault, possible main board or tcon, Im sure someone else has worked on these and can provide you with more information.

[tom66]

Re: Polaroid 3211-TLXB Cap Issue

I have seen that cap go bad on this model before. To confirm, you need to lift the cap up slightly and press on the plastic disc. If you can depress the disc the capacitor is probably OK; if not, you may have a problem with it.

[Ifixthings]

Re: Polaroid 3211-TLXB Cap Issue

I lifted the cap from the glue and pressed the bulged part it had very little flex. I plan on starting with the cap b/c swapping it seems like the easiest place to start.
Can I throw a 150uf 450v 105c Cap from radioshack in there if they have one? Will any cap with this rating have the same impedance and ripple current specs?

Edit: I have a cheapie Digital multimeter (craftsman), if anybody could point me in the direction of some testpoints/ usual readings.

[tom66]

Re: Polaroid 3211-TLXB Cap Issue

Don't use radioshack caps, they are no good... and they cost a fortune, for absolute rubbish.

This ought to work: http://www.digikey.com/product-detai...378-ND/3134334
$4.10 + $2.75 shipping.

[Ifixthings]

Re: Polaroid 3211-TLXB Cap Issue

Thank you Tom. Should I also replace EC17 and EC18 (the 2 smaller brown caps to the left of the heatsinks)? I saw a post where a user replaced these 3 caps and it fixed his TV. But these aren't bulged, burnt or leaking.

[tom66]

Re: Polaroid 3211-TLXB Cap Issue

You can if you like, for reliability only.
http://www.digikey.com/product-detai...672-ND/1246001

[Ifixthings]

Re: Polaroid 3211-TLXB Cap Issue

I had those in my cart, ah the small victories lol. I just noticed that there are voltages written on the power board. The connector in red looks like it provides power to the logic board. The bottom right is AC in, and the white connector on left I think it's power to the panel (not sure) ? the one next to connector in red I dunno?

Can I unhook all the connectors except AC in and check the voltages out of the red connector ? Will I burn something up by not providing a load? Is it better to leave everything hooked up and get a lead into the connector? Also the connector in red has 3 grounds and an aground. When taking readings can I use the chassis for ground?

[vinceroger69]

Re: Polaroid 3211-TLXB Cap Issue

i would leave everything connected turn on the tv into the fault conditon then use the chassis as ground and push the red probe down the side of each wire to test the voltages test on dc volts see if they match whats printed on the board

[Ifixthings]

Re: Polaroid 3211-TLXB Cap Issue

I figured that's the best, if I got bad caps I just don't want to fry something else. Thanks for the info I will give this a try and report back.

[Ifixthings]

Re: Polaroid 3211-TLXB Cap Issue

Here's the update. Problem started as wife saying tv screen went black while front panel LED stayed lit. Unplugged TV for an hour plugged it back in it power up and the blue no signal screen looked perfect for a couple of secs then screen went white.

As of this morning the TV has been unplugged for a couple days and I have been trying to research parts, diagrams and possible problem. Thanks again to those that got me this far. I ordered the 2 10uf 450v caps and the big filtering cap from digi key. With the TV off and unplugged I tested F2 which was good and D10 which was also good- but I never unsoldered a leg. (these were issues in other polaroid TV threads)

Today I hooked up a blu-ray player and now the screen lights up completely white with sound, you can kind of see the images and menus do work.
I used the chassis as ground and took readings from the power out to main board (red connector in previous pic) here are the readings from left to right:

Board marking/ Actual reading
20V- 25.1vdc
12V- 12.1vdc
5VSB- 5vdc
STB- 4.5
These were taken while the movie was playing with fault present.

[Ifixthings]

Re: Polaroid 3211-TLXB Cap Issue

I been trying to find a schematic for this TV but have been unsucessful. I attached a pic of the main board and noticed some corrosion on the top right of the pic, I haven't had time to take apart the tv further was wondering if anybody knew what was in that area of corrosion? Also the connector where the camera flash is, is JP4 which I'm pretty sure goes to the TCon. Anybody know what pins to test to see if the main board isn't sending voltage? Since i'm not missing any voltages on my power supply (the 20 is reading high at 25v and I don't know tolerances for this) I think it's the TCon since everything else on the TV works, but I have no experience with TVs and would like to prove it without throwing parts at this.

Besides testing the power board for an AC ripple are there any other testpoints/checks I could perform with an O-Scope?

[vinceroger69]

Re: Polaroid 3211-TLXB Cap Issue

before messing with it too much i would wait for the new capacitors to come and replace them first ive had a set with those two same caps gone causing simalar issues once replaced all was fine if youve never replaced capacitors before just make sure you fit the negative side as per how you remove it ive just had a set where some one recapped a board and two caps they replaced was around the wrong way!!!.

[Ifixthings]

Re: Polaroid 3211-TLXB Cap Issue

I will replace the caps, I just got them. It's crazy how much smaller the 105uf cap is! Fingers crossed this is the problem.

[Ifixthings]

Re: Polaroid 3211-TLXB Cap Issue

So I replaced EC17 EC18 and the bulging 150uF cap paying attention to polarity, and the TV still has the white screen, and 20V lead is still reading 25V. I tested the old caps with ESR meter and 150uf cap read 142uf, 10uf caps read 9.5 and 9.8 I believe . I don't know if I just didn't notice before but when the TV first turned on there were horizontal lines in the picture then just solid white, then when a movie plays you can see the picture just super washed out.

Any way for me to now see if the main board is sending power to the Tcon ? Expected voltages? I want to check as much out now before I completely disassemble the TV

[vinceroger69]

Re: Polaroid 3211-TLXB Cap Issue

theres a lead going from the main board to the tcon i would try to remove and refit it as it could be a bad connection i guess.

[Ifixthings]

Re: Polaroid 3211-TLXB Cap Issue

The last pic I posted is the main board. Where the flash reflects is the connector JP4. Next to that connector are 2 posts. Are they for shorting a signal ? or test points? they are directly to the left of the connector in the pic.

[Ifixthings]

Re: Polaroid 3211-TLXB Cap Issue

been real busy so today is the first day in a long time I touched the TV...screen still shows faded polaroid screen at startup but turns solid white after- no picture....

until I plugged it in again and pinned out connector coming from main board to TCon and now the pic is washed out but visible. Pinout while hooked up from top left to right, then bottom left to right
4.6 4.6 0(black wire) 1.1 1.2 1.5 1.4 1.2 two wires far right are 0
4.5 4.5 0(black) 1.5 1.4 1.3 1.3 1.5 two wires far right 0

the wires that are at the far right of the connector on top are a gray wire and a black wire, on the bottom it's a blue wire and a black wire. my question is are the colored wires grounds or missing voltages ? because the main power board has only has 4 black ground wires going into the main board.
are the rest of the voltages normal ? I'm trying to narrow down if it's the TCon

EDIT: the pic is after I pinned out the connector....the best it has looked since I started

[mmartell]

Re: Polaroid 3211-TLXB Cap Issue

Is this not an AS15 failure ?

[Shinju]

Re: Polaroid 3211-TLXB Cap Issue

Looks like a Gamma issue, These Polaroid TV's have major power supply failures. Not constructed very well. I have one sitting that I replaced all the non working components on the board and it was working fine for a few hours and now the sucker after the Polaroid logo shuts the CCFL's off.

Ugh..

Good luck with this beast!