Re: LG 50PJ550 clicking/not staying on

Sorry it ended up being a busy weekend and I didn't get a chance to work on it. I tested the power supply as mentioned (disconnecting cables) and it stays powered on without the YSUS/ZSUS boards connected and the voltages match the service manual. I am testing the YSUS/ZSUS boards now. Thank you for the suggestion on the YSUS board failing more often. It does look like I have a short on the ZSUS with Q20 going to ground. I have attached images of the Power Supply and will update on the ZSUS as soon as I get replacement parts. Thanks!...

Re: LG 50PJ550 clicking/not staying on

Thanks for the suggestions. I will post a picture of the power supply board shortly. It is the one with the 2 resistors in the upper right (5W22ROJ, Resistors R927 and R929). I tested them and they appear to be fine (22Ohms). I was doing some testing last night and may have a short on the ZSUS board if that makes sense for the symptoms I am having.

Re: LG 50PJ550 clicking/not staying on

Thank you for the reply and for the link to the service manual. I started on the Power Up Boot troubleshooting measuring with a multimeter and below are the results. For plug 301 and 812 I have placed my measurements in brackets after the legend on the circuit board. I have to unplug the M_ON wire for the set to power up long enough to take these measurements. Thanks again for any advice and I am wondering on the measurements for IC301 (power board) as they seem off however the power supply output looks correct.

P301 (plug 301)...

I recently received a LG Plasma TV (50PJ550-UD) which clicks upon pressing the power button however after another clicks turns off. There is no image displayed during this time. I attempted to troubleshoot and unplugged both the YSUS and ZSUS board (the ZSUS board plugs in to the YSUS on this model). With the ZSUS board unplugged the power stays on. With the YSUS connected the 2 clicks and then power down occurs. I replaced the YSUS board and buffers thinking this was the issue however the issue remained. I also thought it might be the power board which I replaced and still the same issue. I was...

Re: New Members - please post your introductions here

Hello everyone. I am new to the site and decided to register as I have repaired several different electronics over the years and a recent television has proven difficult to troubleshoot.