Re: LG 42PC3D - UD Turns on and off till power is unplugged

Got it handled. scabbed 2 5v fans out of an old laptop fan. Connected power to the molex into the ysus and zsus. Tv has been on for 3hrs. Hasn't shut down once and heat sinks on the ysus and zsus are slightly warm to the touch. Thanks to everyone for their advice.

Re: LG 42PC3D - UD Turns on and off till power is unplugged

Tom66, bypassed optos. No on and off... Looking good so far. Thanks for the suggestion. I want to put fans on the ysus and zsus. Should i pick up power from any particular place? Thanks again for the opto bypass!

Re: LG 42PC3D - UD Turns on and off till power is unplugged

Thanks Tom, was hoping for a magic bullet answer. My power supply board is the exact same as the board you posted in the other thread.

Re: LG 42PC3D - UD Turns on and off till power is unplugged

Good news sort of, i replaced the fuse and plugged ysus back in. Picture works. Metered the ac det. Stand at 4.89 volts when the tv is on or off. while I had the meter hooked up the tv cycled off and the volts dropped down to .38 I had to manually turn the tv back on and the voltage went back up to 4.89.

Tom66, I found an ac detect post of your in another thread. Could it be that the ac detect is sending a surge to the ysus when the power cycles n and off causing the ysus to fail? I noticed that the fix involves...

Re: LG 42PC3D - UD Turns on and off till power is unplugged

Thanks for the quick replies. Unplugged ysus. Power stays on. Vs voltage 188.6 and 188.5. Both in and out of the power supply. I metered power coming out of the power supply to the ysus at 5.21 volts. Metered the power in to the ysus at 5.19 volts. Plugged ysus back in and popped the fuse....... UGH!!! heading to get some fuses. If that works I'll unplug the y buffer....

Hello all,
I've been scouring the forum looking for a solution to my problem. Please forgive me if this question has already been answered. Here's the back story on the unit. The power on/off happened intermittently for about 6 months till the set popped and the picture went out. I traced it to a bad y-sus board. I purchased a new board and the tv worked fine for about a month.

Turned tv on a pop. This time the z-sus board went. I had the z-sus board repaired by a reputable business mentioned n this site. About a month after the z-sus board was replaced, pop. Y-sus board...