LG 37LC02R screen go nuts temporary

[PowerAmpFreak]

A friend of mine has a LG LCD-TV model 37LC02R which may work properly for months but occasionally the screen goes all weird flashing on and off fast.
The sound is all present.
Would this be an indication of screen failure or perhaps inverter problem?
Any advice is appreciated. He also mentioned I could buy it in this state, but don't know if this is repairable or not.

[PlainBill]

Re: LG 37LC02R screen go nuts temporary

A friend of mine has a LG LCD-TV model 37LC02R which may work properly for months but occasionally the screen goes all weird flashing on and off fast.
The sound is all present.
Would this be an indication of screen failure or perhaps inverter problem?
Any advice is appreciated. He also mentioned I could buy it in this state, but don't know if this is repairable or not.

I'd be cautious too. A lot depends on the exact nature of the symptoms.

Possible scenario 1: Usually when the back of the TV is off there are a few points where you can see the backlights 'leaking' through openings in the LCD panel assembly. If the backlights are flashing on and off, that is probably an inverter problem. Probing the BL_ON and Bright pins would be useful. IF both lines are stable, this is an inverter problem, and should be fixable.

Possible scenario 2: The backlights stay on steadily, the screen alternates between white and a normal picture. This may be a T-con failure, or a problem with the panel itself.

Possible scenario 3: The backlights stay on normally, the screen alternates between a normal picture and static. This is most likely a problem with the main board.

I don't know how much your time is worth (mine's dirt cheap), but diagnosing intermittent problems like this can be very time consuming. Obviously, if you open it up, find and replace a number of bulging caps, and reseat all cables, then it works perfectly, you should be happy. Even replacing the T-con or inverter and getting a working TV could be profitable. But spending 20 hours on it without identifying the failing part would not be profitable.

PlainBill

[PowerAmpFreak]

Re: LG 37LC02R screen go nuts temporary

Great input, Bill. I decided to keep my fingers away from this one.
Those intermittents are often very very time consuming, like you say...
Better stay away.