Proscan PLDED3992A-C led failure?

[dick_barton]

Re: Proscan PLDED3992A-C led failure?

You can now use your led tester to find where the problem is with the top led strip.

[jose6326]

Re: Proscan PLDED3992A-C led failure?

You can now use your led tester to find where the problem is with the top led strip.

how????

i disconnected the top LED strip and probed it with tester and the strip does not light up

i did the same with the other strips and they do light up

do i have to de-solder the LEDs?

[dskall]

Re: Proscan PLDED3992A-C led failure?

You will have to probe through coating around each one. Trial and error to find +and- for each led. You don't need to check each led if you are going to replace strip.

[jose6326]

Re: Proscan PLDED3992A-C led failure?

I cant find replacement strips so i will replace the individual faulty leds.

I removed the diffusers and tested each led

I think i found the faulty led on the end.
Plus the burn mark on the back of the strip is probably a good indicator lol

[jose6326]

Re: Proscan PLDED3992A-C led failure?

At what temperature and air speed do you use the hot air gun on the rework station?

[dskall]

Re: Proscan PLDED3992A-C led failure?

I use around 260c. With strips off the panel you can heat from bottom. I leave strips attached and heat from top. You just want to minimize heating led itself and melting. I heat strip till solder on pads melt and then drop led on and heat a couple more seconds. I also replace lens with led lit so I can center it over led so you minimize bright spots on screen.

[dick_barton]

Re: Proscan PLDED3992A-C led failure?

If you warm up the led strip it helps to soften the glue sticking it to the metal chassis.
I heat up from underneath the faulty led using the hot air gun but basically identical to

https://www.youtube.com/watch?v=EZVQKEp6jxk

[jose6326]

Re: Proscan PLDED3992A-C led failure?

i tried using the heat gun and it didnt work

i was afraid of using to high of a temp and possibly damaging the strip

but i will try again

thanks for the help

[dskall]

Re: Proscan PLDED3992A-C led failure?

Some leds weld themselves to the pads and may be difficult to remove. The strips are pretty heat tolerant.

[jose6326]

Re: Proscan PLDED3992A-C led failure?

i was able to get it off.
i had to raise the temp and lower the fan speed. i did burn it a little more but not bad



thanks