LED DLP with puzzling behavior


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TV Repair Jedi
TV Repair Jedi
Posts: 85
Joined: Fri Apr 17, 2015 7:07 pm

LED DLP with puzzling behavior

Postby appleads » Fri Dec 02, 2016 8:32 pm

Okay, so I've fixed about 20 or so of the HL-S and HL-T series of Samsung DLP's. I've encountered some that were easy to fix and others that were a real PIA. Here's my latest challenge. I bought for next to nothing a "white dot" HL-T6187sx/xaa

Samsung LED DLP. Swapped out the bad DMD chip for a new one, and noticed that the capacitors in the power supply were starting to bulge, so I de-soldered 5 of those and replaced them with new. However, now I am having trouble getting the set to behave normally. I am using component video input from a cable box until the HDMI cable I ordered on line arrives. Let's assume the set is at normal "rest" state, with the red stand-by LED lit. When I go to turn the TV "on" it does not light up. BUT, if I then unplug it and plug it back in I can get it to display a picture. Furthermore, on some channels the image will FREEZE, but the sound will continue. If I change channels, the picture will then go back to "normal." Often, my Samsung remote will not seem to function, but other times it works just fine. By unplugging and then plugging the set back in, I seem to be able to "reset" the tv and get it to work, freeing it up from a dormant/frozen state. Before I start throwing new boards into it, I'd sure like to know what's causing the image to not generate upon start up, to freeze when first viewed, to be "reset" by pulling power and then restoring power, and to work perfectly once it gets "going." Any thoughts or suggestions would be most appreciated.

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TV Repair Jedi
TV Repair Jedi
Posts: 85
Joined: Fri Apr 17, 2015 7:07 pm

Re: LED DLP with puzzling behavior

Postby appleads » Thu Feb 23, 2017 4:27 am

Here's an update on this latest adventure.

Swapped out the power supply for a good one from another set. Improved things slightly but did not fix.

Tried a new LED driver board/assembly. No change in behavior

I'm now going to change our the main "brain" or motherboard, as soon as I get one that has the right cable and not a ribbon connection.

I'll let you know how that works.

Here's what the tv does.

Red light, standby state.

Hit "on" nothing happens for a while, then I get a picture (this delay should be telling me something)

Picture is fine for a little bit then it freezes into a compressed zigzag of lines.

Turn off set, or power off.

Turn on.

Works fine.



Go figure.


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