Hisense 40K360MN dim picture like in power saving mode

[CapLeaker]

Re: Hisense 40K360MN dim picture like in power saving mode

Did you check it if there is a short to ground maybe?

[budm]

Re: Hisense 40K360MN dim picture like in power saving mode

I will have to download the picture and start tracing this weekend, I may ask for more closed up pictures later on.

[nortnil]

Re: Hisense 40K360MN dim picture like in power saving mode

Sounds great, thanks budm!!!

[budm]

Re: Hisense 40K360MN dim picture like in power saving mode

"I was also wondering about C869 having 0VCD when I measured using the chassis as ground." OK, I took a quick look at the circuit around C869, it is not ref. to the chassis GND so you need to measure directly right at the two legs.

[nortnil]

Re: Hisense 40K360MN dim picture like in power saving mode

Okay, thank you for looking. Right at the legs I got 138VCD then.

[budm]

Re: Hisense 40K360MN dim picture like in power saving mode

OK, I traced out the board, the LED STRINGS are connected in series to form one long string, so if you measure the Voltage between point A and Point B when the TV is first turned on, you should see very high Voltage and if you disconnect the LED connector and do the measurement again, the Voltage should also shows the same readings.

[nortnil]

Re: Hisense 40K360MN dim picture like in power saving mode

Wow, you did that fast.

From A to B with the LED connected it shot right to 460VCD and then moved to 463VCD and stabalized shortly after

With the LED connector disconnected I got 467VCD.

[budm]

Re: Hisense 40K360MN dim picture like in power saving mode

OK, the LED strings has open connection either at the connectors inside the panel or the LED inside the panel.

[nortnil]

Re: Hisense 40K360MN dim picture like in power saving mode

Okay I guess it is time to take this thing apart. Any tear down guides I should look at first, or any general tips I should be aware of?

[budm]

Re: Hisense 40K360MN dim picture like in power saving mode

They are no standard on how the panel is put together so I have no suggestion for this one.
BTW, who sells this brand? WALMART?

[nortnil]

Re: Hisense 40K360MN dim picture like in power saving mode

Yeah I think so. My friend gave it to me after it crapped out to tinker with.

Guess it's time to go slow and carefully. I'll report back what I find.

[nortnil]

Re: Hisense 40K360MN dim picture like in power saving mode

OK, the LED strings has open connection either at the connectors inside the panel or the LED inside the panel.

Wuahaha WOW!!! I was not prepared for the front glass/actual LCD panel to come off from the backlight like that!

You sir are a genius!!! One of the LED strips was slightly unplugged. I plugged it back in and now it is up and running again. (I just realized I probably should have put some tape or glue on that while I was in there)



Do you have a paypal or something I can make a donation to? I would like to buy you a beer.

Thank you again for all of your help!!!!

[budm]

Re: Hisense 40K360MN dim picture like in power saving mode

Nice, that was fast, only 32 threads. Did yo take the pictures of the connectors? I am sure there are more out there with the same problem like this one.
Glad to hear it did cost any money for parts.
It looks small for 40" TV.

[nortnil]

Re: Hisense 40K360MN dim picture like in power saving mode

No I planned to, but I started to freak out about dust once I saw how the layers separated. So I tried to move as efficiently as possible.

Basically the LED cable going into the panel itself separates into two pairs, blue and black and red and white, that terminate into little two prong molex connectors. On the right side (from the front of the TV) is the LED strip. One plug goes to the top, and the other to the bottom. The one at the top was visibly askew.

I plugged it back in and then hooked the power supply, logic board, and power switch up and plugged in the LED power connector to test. In my usual fashion I stared right at the lights to make sure they were working and damn near blinded myself when they came on.


As far as the disassembly, there were about 15-20 small screws that held the front black bezel to the LCD panel. That was what was holding the LCD glass to the backlight.

From there, there were only 4 screws on the bottom of the backlight panel that held the plastic rim on outside of the plastic snaps. I went around and freed all of the snaps and the metal back lifted straight off. I tested it, blew off the back sheet with compressed air, and dropped the metal back on and quickly put it back together.

From a quick visual I don't think I got any smudges or dust inside or around the edges of the panel.

[CapLeaker]

Re: Hisense 40K360MN dim picture like in power saving mode

Not too long ago there was another thread with exact the same problem. The cable to the LEDs wasn't plugged in properly.