Re: LG 42PC3D Main Board Problem



Thanks, but the menu tree settings on this TV do not have a "Last State" option.

I found the service manual for the -UE version.

It shows SW4001 in the ATSC Tuner section as "EJTAG_RSTb" on pin 1 of IC4004, which is a voltage sensor. It appears to pull the EJTAG line and pin 1 of IC4004 to ground when pressed. Normally it appears that these are at 3.3Volts.

There is a 10uF capacitor in this circuit. I think I'll try replacing it and see what happens.

...

I have a question regarding an LG 42PC3D-UE main board.

Initially I suspected the SMPS so I replaced all the electrolytics on the secondary side just as a precaution. All the voltages are present and correct.

This TV powers up, there is screen glow, but it won't respond to commands or accept inputs.

That is, until I press SW4001. This is a small momentary switch located just below and to the right of the RF module on the Main Board (this is the UE version so there is only one main board). As soon as this switch is pressed the TV accepts input, displays...

Re: New Members - please post your introductions here

Hi,
I'm Ed from Lake Jackson, TX. I'm a hobbyist and a tinkerer. Sometimes I need a little help with TV repair.