LG L1710S 2 seconds to black? (pics)

[TransAm84]

Re: LG L1710S 2 seconds to black? (pics)

*UPDATE* I went ahead and replaced some of the caps. I did not replace the big main cap or the 2 smallest ones. I replace C3(470uf 25v) and 3 of the 4 mid sized caps that are grouped together at the corner of the board. I did not replace the biggest one of that group (1000uf 25v) because i did not have one here. Anyways, that did not fix the problem. Still getting about a .5 second flash of picture then the screen goes dark. Thanks again for all the help so far.

[jetadm123]

Re: LG L1710S 2 seconds to black? (pics)

Looks like you've checked all the usual suspects and I'm of the mindset that either U1, the OZ960 ccfl inverter controller has a problem with the feedback circuit causing it to shut down, or the chip itself is bad. Based on my observations, the success rate for repairing this part of the inverter has been very low. You can at least check the following things:

Be careful when placing your probes, as the pins of U1 are close together. Better if you can place your probes on components connected to the pins themselves.

Capacitor C18 is connected to pin 1 on U1. Pin numbering follows the "U" pattern. Pin 5 is the power supply input to U1. Typical voltage for pin 5 is around 5V.

Pin 3 of U1 is the ENA (enable) input and should read around 2.0V-3.3V.

With power OFF, check small capacitors C9 and C10 for shorts. They're located off of pins 4 and 5 of U1.