Sharp LC-40LE433U triple images and distortion

[omni550]

I 'found' a Sharp LC-40LE433U that a neighbor had put out on trash pick-up day.

I brought it home, hoping to learn a bit more about flat screen TVs by troubleshooting it and getting it working (if needed parts are available and not too pricey). It's my first time working on a flat screen TV, so please 'speak slowly'.

It looks to be in good physical shape (no obvious damage).

Initially, after I plugged it in, all it would show was a solid red power light.

I found a service menu online and pushing a sequence of buttons got me to these next 2 screens ("No Signal" and what appears to be a Menu screen). As you can see, the images are quite distorted. They are also in triplicate.

I took off the back cover and took a look around. (see photos). Nothing looks glaringly obvious or out of place.

Any suggestions as to what might be the issue? What I might try next? OR is this a lost cause?

Thanks,

omni

[budm]

Re: Sharp LC-40LE433U triple images and distortion

If I remember correctly, it may be bad caps on this FRC board.
https://www.badcaps.net/forum/attach...5&d=1453951275
You can try heating this board with hair dryer to see if the symptom changes.

[omni550]

Re: Sharp LC-40LE433U triple images and distortion

If I remember correctly, it may be bad caps on this FRC board.
https://www.badcaps.net/forum/attach...5&d=1453951275
You can try heating this board with hair dryer to see if the symptom changes.

Thanks, budm, for the quick reply.

As it's getting late here, I'll try this tomorrow and will report back.

omni

[omni550]

Re: Sharp LC-40LE433U triple images and distortion

budm,

I tried applying heat to the FRC board with a hair dryer, as suggested.

Initially, I didn't notice much change in the display (although the chassis in that area got warm/hot to the touch), so I tried the hair dryer again.

After a few minutes, I was watching the display and noticed some random red coloration in the background of the black & white "No Signal" screen. As I was getting my camera ready to snap a photo, the TV shut itself off, leaving a solid red power light.

I tried restarting the TV, but have not been able to get past the red power light.

I'll wait and let the unit cool down completely and then will try restarting it.

Until then, any other thoughts/ideas?

omni

[omni550]

Re: Sharp LC-40LE433U triple images and distortion

OK...the set has now cooled down.

I tried restarting it.

The TV is back to it's "usual"...a distorted black and white "No Signal" displayed in triplicate....and a random blue horizontal line (approx. 1/2" high) across the screen every now and then. (No sign of the random red coloration the showed-up just before the TV turned itself off earlier.)

Would this test indicate that the FRC board is (or bad caps on it are) the culprit?

omni

[omni550]

Re: Sharp LC-40LE433U triple images and distortion

I found a video online where a service tech mentions the use of a hair dryer to heat up a board to temporarily bring it back to life, which would indicate possible bad caps.

When I heated up the FRC board in the Sharp TV initially, nothing much changed. Then when I went back and reheated the FRC board some more, I induced some random red coloration on the B&W "No Signal" screen before the set shut itself off. I had to let things cool down before I was able to turn the TV on again.

I'm not sure if this "test" now proves that the FRC board needs replacement or should I pursue something else in troubleshooting this TV?

omni

[budm]

Re: Sharp LC-40LE433U triple images and distortion

It is tough troubleshooting without much of the service manual.
When caps go bad the ESR will go up and cause the circuit to malfunction, so when you heat it up if the caps are not too far gone, the ESR will come down then the circuit will operate again.
You may want to look around to how much the FRC board is or try recaping the whole FRC board. You have about 9 electrolytics caps on that FRC board.
I also wonder if it has correct DCV feeding that FRC board. The pin are labeled so you can verify the Voltages.
Board is only $10.
http://www.shopjimmy.com/sharp-ti122...ital-board.htm

[omni550]

Re: Sharp LC-40LE433U triple images and distortion

Thanks, budm.

Rather than recapping the FRC board, I think a new board for $10 might be the easier way to go.

I'll attempt to check out the DCV feeding the board.

omni

[omni550]

Re: Sharp LC-40LE433U triple images and distortion

I took a look around and I'm not sure where to check the DCV to the board. Can someone direct me, please? Thx.

omni

[omni550]

Re: Sharp LC-40LE433U triple images and distortion

It is tough troubleshooting without much of the service manual.
When caps go bad the ESR will go up and cause the circuit to malfunction, so when you heat it up if the caps are not too far gone, the ESR will come down then the circuit will operate again.
You may want to look around to how much the FRC board is or try recaping the whole FRC board. You have about 9 electrolytics caps on that FRC board.
I also wonder if it has correct DCV feeding that FRC board. The pin are labeled so you can verify the Voltages.
Board is only $10.
http://www.shopjimmy.com/sharp-ti122...ital-board.htm

budm,

I ordered and installed the FRC board as you suggested.

Success! No more triple images and a good picture!

I've attached a screen shot (photo of a car commercial).

Thanks for your spot-on suggestion.

omni

[budm]

Re: Sharp LC-40LE433U triple images and distortion

Thanks for the follow-up, I was surprised that the board is only $10!