Need help identifying this resistor (LG power supply)

[ecallenil]

This is a power supply from a 32" LG LCD TV that stopped working after a lightning strike. I can't seem to find these resistors anywhere. Further the color bands don't really match anything I've seen. Any help would be GREATLY appreciated!

Power Supply: LT32D-2

I have two pictures. One shows the burnt resistor (R1010) and the other picture shows a good resistor with the same color bands (R1026)

[Mad_Professor]

Re: Need help identifying this resistor (LG power supply)

looks like a 10k with a 10 or 15% tolerance, if I were you I would test the resistance of the good one with a multimeter to confirm.

Also something struck by lighting is never good, GOOD LUCK! I hope this helps.

[ecallenil]

Re: Need help identifying this resistor (LG power supply)

looks like a 10k with a 10 or 15% tolerance, if I were you I would test the resistance of the good one with a multimeter to confirm.

Also something struck by lighting is never good, GOOD LUCK! I hope this helps.

Thanks. I assume I'd have to pull the good one out of the circuit to test, correct?

[start2011]

Re: Need help identifying this resistor (LG power supply)

This is a power supply from a 32" LG LCD TV that stopped working after a lightning strike. I can't seem to find these resistors anywhere. Further the color bands don't really match anything I've seen. Any help would be GREATLY appreciated!

Power Supply: LT32D-2

I have two pictures. One shows the burnt resistor (R1010) and the other picture shows a good resistor with the same color bands (R1026)

Both look like 0.1 ohm 1W

[budm]

Re: Need help identifying this resistor (LG power supply)

That is a 0.1 Ohm 5% 1/4W, Flame proof Metal Oxide (MOX) type resistor, they use resistor as a fuse, very common practice in the power supply design. You can use 1/2W instead.

[budm]

Re: Need help identifying this resistor (LG power supply)

By the way, you should Ohm out one end at a time to ground to see if you have short circuits, otherwise you may blow the new resistor. Do not use Carbon film type, it is not flame proof.

[ecallenil]

Re: Need help identifying this resistor (LG power supply)

That is a 0.1 Ohm 5% 1/4W, Flame proof Metal Oxide (MOX) type resistor, they use resistor as a fuse, very common practice in the power supply design. You can use 1/2W instead.

Thanks! That's what I was thinking. In my searches I've seen references to "fuseable resistors" Please forgive my ignorance but would this one work? I can't seem to find the 1/4 or 1/2 watt .1 Ohm resistors anywhere. http://www.tristatemodule.com/p-1025...-resistor.aspx

[budm]

Re: Need help identifying this resistor (LG power supply)

Sometime they refer to fusible resistor. You can use 0.22 Ohm 1/2W instead.
http://search.digikey.com/scripts/DkSearch/dksus.dll

[budm]

Re: Need help identifying this resistor (LG power supply)

Oops, the link above did not work right.
http://search.digikey.com/us/en/prod...2BCT-ND/614253

[ecallenil]

Re: Need help identifying this resistor (LG power supply)

Thanks so much to everyone who replied.... and on a Friday night! Everyone here is so helpful. Thanks Again!

[ecallenil]

Re: Need help identifying this resistor (LG power supply)

Oops, the link above did not work right.
http://search.digikey.com/us/en/prod...2BCT-ND/614253

Well, I replaced the resistor with the one you linked to but as soon as I plugged the TV in, the resister blew. Any advice on where to look next assuming that I used an appropriate resistor? I know enough about electronics to be dangerous but I'm not sure what could be making this resistor blow unless something down the line is shorted out or something. Any help is appreciated. I can post better pictures of the board if necessary.

[budm]

Re: Need help identifying this resistor (LG power supply)

That means shorts circuits, next we need to know what circuits that resistor is feeding.
Can we see better pictures of the board of the top and bottom, closed up pictures of the traces feeding and leaving this resistor?
What is the LG TV model/chassis number?

[ecallenil]

Re: Need help identifying this resistor (LG power supply)

Thanks for your help. I have attached pictures, both full view pictures and pictures of the board divided into thirds (top and bottom) If you need better pictures of any one part please let me know. I can zoom in on these really well on my computer however I'm not sure what they'll look like once uploaded.

The TV is a Westinghouse LTV-27w7 HD. For some reason I thought it as an LG until I looked at the model number so sorry for the incorrect title.

Again, the resistor that is blowing is R1010 which can be seen along the top of the board right above the 2 large 200v capacitors.

Again, thanks for the help... I REALLY appreciate it!

[budm]

Re: Need help identifying this resistor (LG power supply)

Please see the PDF, I need the closed up of the red area, I believe it may have shorted out MOSFET's in the 24VDC HALF-BRIDGE TRANSFORMER drivers.

[Toasty]

Re: Need help identifying this resistor (LG power supply)

Resistor is in the drain of Q1009.

Q1009 & possibly Q1011 are bad. Q1009 is most likely shorted.
When replacing, replace -both- FETs

Good chance C1025 is also bad. Gray square cap between the two FETs.

Reflow the pins on that transformer (T1002) below them. Looks like a crack around the lower pin in the back shot.

[budm]

Re: Need help identifying this resistor (LG power supply)

Toasty, you have really good set of eyes! the pictures look so out of focus, I also suspect that he may have shorted out MOSFET's.

[Toasty]

Re: Need help identifying this resistor (LG power supply)

Nah.

http://imagezoom.yellowgorilla.net/

Plus, the 2 lower back pics are much clearer.

[ecallenil]

Re: Need help identifying this resistor (LG power supply)

Here are the pics requested. I am using a better camera this morning so things should be better. I am also concerned about the solder covered traces (I think) in the lower left corner of picture "closeup2" For some reason the solder seems to have to not covered them completely. I would think this isn't a problem because the copper (I think) is still good but there has to be some reason for the solder, right?

[budm]

Re: Need help identifying this resistor (LG power supply)

Please see the PDF, you need to Ohm out (all three legs combinations) of the two MOSFETs Q1009, Q1011 for shorts.

[ecallenil]

Re: Need help identifying this resistor (LG power supply)

Please see the PDF, you need to Ohm out (all three legs combinations) of the two MOSFETs Q1009, Q1011 for shorts.

Forgive my question but do I need to remove them from the circuit for this test? I assume I do.