Help to fix my LCD TV!

[dr_jared88]

I have a 47" Insignia LCD TV that stopped working and I am trying to fix it. My dog chewed the power cord to the TV and I believe it may have shorted and blew something inside the TV.

I replaced the power cord and the standby light comes on. When I turn the TV on, the power light goes from red to blue indicating the TV is on however there is no display. I've tried a flashlight on the screen to see if maybe it's the back light but it doesn't appear to be displaying anything.

I searched around a bit and read that the issue is likely a blown capacitor so I decided to open up my TV. I looked all over for a cylinder that is bulging but didn't find anything. I did find a green disk that looked slightly burnt but I don't know what it is. My guess was a ceramic disk capacitor but searching google and the zig zag line on the circuit board makes me think that maybe it is a thermistor.

My question is can anyone here identify what this is and if it looks blown? I am going to put on ohm meter on it tonight to see if anything gets through it.

https://docs.google.com/open?id=0B7eiX_7dYHCKYnUySUxuc1pMRk0

[dr_jared88]

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[Zero102]

That is a thermistor, probably fine. Check the red round fuse beside it. If you shorted the power cord it is possible that the fuse burned at the same time. Usually the main fuse will keep any lights at all from turning on, so check the board for other fuses (sometimes small and green like a green resistor), they should all be labelled with F and a number, like F101 or F301 or something.

If that fuse is good get good pics of the top and bottom of the inverter/power board and post them up, or post them over at the badcaps forum, some pretty knowledgeable guys there.

[clem24]

Did your dog learn a 120V lesson? Is (s)he scared of power cords now? :D

[dr_jared88]

Originally posted by Zero102
That is a thermistor, probably fine. Check the red round fuse beside it. If you shorted the power cord it is possible that the fuse burned at the same time. Usually the main fuse will keep any lights at all from turning on, so check the board for other fuses (sometimes small and green like a green resistor), they should all be labelled with F and a number, like F101 or F301 or something.

If that fuse is good get good pics of the top and bottom of the inverter/power board and post them up, or post them over at the badcaps forum, some pretty knowledgeable guys there.

Thank you I will take a look at that when I get home and take some pictures.


Originally posted by clem24
Did your dog learn a 120V lesson? Is (s)he scared of power cords now? :D

I am assuming he must have had a jolt but I don't think he learned his lesson... Stupid expensive dogs.

[dr_jared88]

Here is a couple more pics if it helps.

https://docs.google.com/open?id=0B7eiX_7dYHCKWHZCVFZaUmVNVkk

https://docs.google.com/open?id=0B7eiX_7dYHCKYWlXb3FaMG5KR1k

[Zero102]

It is really hard to spot whether the lcd is displaying something even with a flashlight on TVs due to the much thicker plastic and coatings / textures on it.
If the power LED indicates the TV is on then the logic board is probably coming up okay, I would say the first thing to check is power to and from the backlight/inverter board. Those pictures aren't high enough resolution to say much about what to test on them, and I don't see the inverter components on that board either.

Check out badcaps, see if anybody else has had a similar problem with a similar TV, if not, read their guidelines for posting pictures and post some clearer higher resolution pics without flash, and see if you can track down the inverter board as well. That is, of course, unless the tv is led backlit, you didn't give a model number so I don't know.

**EDIT**
I re-checked your last picture and I can see the high voltage leads for the ccfls behind the board you were taking pictures of so the inverter board is there and the tv is not led backlit.

Check the output voltages of the power supply board. If they are all good, check both the power and inverter boards over for fuses and meter them out.