Skyworth 40E58 no display

[yobbgsm]

Hi Experts,

I have a here, a 40" LED TV brand is skyworth, I thought it was a backlight issue since I can see a display using a torch. Voltage are good up to 37V output to LED. I opened it up and test all the backlight to find out nothing is busted. All are good. I rehot the TPS61196 Led dirver IC, assembled and test, seeing dispaly and I even the set the backlight but after closing the unit and boot up again, same issue occur, ni display again likeno backlight. Do you think the Led driver IC is the culprit? Voltage are good to the backlight. Any idea is very much appreciated.

Pics attached of the board.

[budm]

Re: Skyworth 40E58 no display

It looks like the boost converter is not working, I expect more than 37 Volt.
Put the meter probes on the two legs of either one of those tow lytics cap (CP2, CP3: 100uf 100VDC) laying on its side then turn the TV on to see how high it goes up too and then wait 5 seconds to see how low it goes down too; then remove the LED connector and do the same test and report the results.

[yobbgsm]

Re: Skyworth 40E58 no display

Hi budm,

Your always helpful, appreciate it. So I followed your instructions and got these results.
Caps- 55V high then went down to 30V.

Same result on the LED connector. Do you think there is an issue on the voltage?

Thank you so much!

[yobbgsm]

Re: Skyworth 40E58 no display

Do you guys have a schematic diagram for this model? Thanks.

[budm]

Re: Skyworth 40E58 no display

OK, at least the Voltage Boost converter did kick on for seconds,
Next thing you need to do is to test the Voltage on all 6 wires (6 wires are what I can see) at the LED connector (connector in place).
Start by leaving the TV off and leave Black meter probe on the chassis, then put red probe on one of the 6 wire and then turn on the TV while looking at the meter to see how high the Voltage go up to, record that reading and then turn off the TV.
Repeat the same procedure on the other 5 wires and report your finding.
https://www.badcaps.net/forum/attach...4&d=1508126628
BTW, I can see that the LED connector has the pin labels for each pin but I can hardly see it.

[yobbgsm]

Re: Skyworth 40E58 no display

@budm

Will do and post result. Thank you for your patience.

[yobbgsm]

Re: Skyworth 40E58 no display

This can be close. I resolved the issue, there is a single bulb that I think soon to be busted. It's on and off the reason there is a display sometimes.

[budm]

Re: Skyworth 40E58 no display

When you finished the repair, make sure to turn down the Backlights level (not Brightness) to as low as possible to extend the life of the LEDs, these LED backlights are pushed to the limit so they burn out after a few years or less.

[heavymachines]

Re: Skyworth 40E58 no display

Thats what i did with the samsung we fixed yesterday the backlight setting was maxed out!!!! No wonder why it killed the bulb i replaced. and probably why it wanted to shut down on the replacement.

[autovolt007]

Re: Skyworth 40E58 no display

Hi Experts,

I have a here, a 40" LED TV brand is skyworth, I thought it was a backlight issue since I can see a display using a torch. Voltage are good up to 37V output to LED. I opened it up and test all the backlight to find out nothing is busted. All are good. I rehot the TPS61196 Led dirver IC, assembled and test, seeing dispaly and I even the set the backlight but after closing the unit and boot up again, same issue occur, ni display again likeno backlight. Do you think the Led driver IC is the culprit? Voltage are good to the backlight. Any idea is very much appreciated.

Pics attached of the board.

sir i need a little help here, since you have that same board can you please take a look at the number of the smd transistor at the QP5 near opto? i got the same board and mine is bloated so i cannot see the number. this will be a very big help sir. thank you

[autovolt007]

Re: Skyworth 40E58 no display

this is my board sir skyworth 40e58, anyone here with a board like this i need a little help that one pointed in red arrow what is the number of it? thanks in advance