LG 50PZ550 / Zenith Z50PV220 clicking not power on, troubleshot but not sure

[dbdbdbdbdb]

I opened the back, and if I unplug the Zsus board( EAX63551301), then the TV could power on and I can see some pixels moving on screen(from the pattern I can tell it's the "no signal" moving sign). And I tested the output of power board seems OK.

But if I plug in the ZSUS board, it just keeps clicking 2 or 3 times then goes to standby. There are no obvious swelled caps on all boards, especially the ZSUS board.

Can I just say that board is broken? Is there some advise to trouble shooting some bad components on that board or I just replace the whole ZSUS board? Thank you very much!

[tom66]

Re: LG 50PZ550 / Zenith Z50PV220 clicking not power on, troubleshot but not sure

You can replace the Z-Sus or you can post a picture of it and we may be able to help you repair it.

[dbdbdbdbdb]

Re: LG 50PZ550 / Zenith Z50PV220 clicking not power on, troubleshot but not sure

You can replace the Z-Sus or you can post a picture of it and we may be able to help you repair it.

It's the same board, but not from my TV. thanks!

[tom66]

Re: LG 50PZ550 / Zenith Z50PV220 clicking not power on, troubleshot but not sure

OK, with the board removed from the TV, test across here for ohms. You should see an open circuit if there is no short on the board.

[dbdbdbdbdb]

Re: LG 50PZ550 / Zenith Z50PV220 clicking not power on, troubleshot but not sure

OK, with the board removed from the TV, test across here for ohms. You should see an open circuit if there is no short on the board.

thanks, I will try when I got home.
BTW, there was a "pop" noise when screen went off on the last day I watched it, then I thought something exploded inside. But nothing looks bad after I checked... weird...

[tom66]

Re: LG 50PZ550 / Zenith Z50PV220 clicking not power on, troubleshot but not sure

thanks, I will try when I got home.
BTW, there was a "pop" noise when screen went off on the last day I watched it, then I thought something exploded inside. But nothing looks bad after I checked... weird...

Yeah, that definitely sounds like a Z-sustain failure. It is very common to hear a pop when these boards go bad. Usually, nothing is obviously failed.

[dbdbdbdbdb]

Re: LG 50PZ550 / Zenith Z50PV220 clicking not power on, troubleshot but not sure

Yeah, that definitely sounds like a Z-sustain failure. It is very common to hear a pop when these boards go bad. Usually, nothing is obviously failed.

you are so right, I tested the cap you told me, and it is SHORT...
But I think the 4 caps are in parallel also there might be other components shorted causing the test short...? Is there some way to identify? Thanks again!

BTW, I have a college classmate is pursing his EE Phd at University of Leeds, maybe focusing on electromagnetic fields research stuff...I even think you may know him,hahahah

[tom66]

Re: LG 50PZ550 / Zenith Z50PV220 clicking not power on, troubleshot but not sure

you are so right, I tested the cap you told me, and it is SHORT...
But I think the 4 caps are in parallel also there might be other components shorted causing the test short...? Is there some way to identify? Thanks again!

It's actually just a general test of the board, a convenient point to see if there is a short. In this case, there definitely is.

Post a picture of the underside of the board so I can highlight some MOSFETs and IGBTs to test - the devices on the large heatsinks.

BTW, I have a college classmate is pursing his EE Phd at University of Leeds, maybe focusing on electromagnetic fields research stuff...I even think you may know him,hahahah

Heh interesting - we do have a microwave, photonics and lasers department here. Terahertz technology is something they are pushing - sub-light lasers for medical use apparently. It's pretty cool stuff and it's supposed to be #1 in the country.

[dbdbdbdbdb]

Re: LG 50PZ550 / Zenith Z50PV220 clicking not power on, troubleshot but not sure

It's actually just a general test of the board, a convenient point to see if there is a short. In this case, there definitely is.

Post a picture of the underside of the board so I can highlight some MOSFETs and IGBTs to test - the devices on the large heatsinks.



Heh interesting - we do have a microwave, photonics and lasers department here. Terahertz technology is something they are pushing - sub-light lasers for medical use apparently. It's pretty cool stuff and it's supposed to be #1 in the country.

hi this is the new file, I took off those cooling pads to unveil components, I hope it will help. thank you very much!

[tom66]

Re: LG 50PZ550 / Zenith Z50PV220 clicking not power on, troubleshot but not sure

OK, please test each device which has similar pin connections to the one I have highlighted:

Mentally number pins 1 to 3 (order doesn't matter but be consistent.)

With the board unplugged, set your meter to 200 ohms, and meter across: 1-2, 2-3 and 1-3.

Report your readings for each device.

For now two-terminal devices do not need to be tested, only three terminal ones.

[dbdbdbdbdb]

Re: LG 50PZ550 / Zenith Z50PV220 clicking not power on, troubleshot but not sure

OK, please test each device which has similar pin connections to the one I have highlighted:

Mentally number pins 1 to 3 (order doesn't matter but be consistent.)

With the board unplugged, set your meter to 200 ohms, and meter across: 1-2, 2-3 and 1-3.

Report your readings for each device.

For now two-terminal devices do not need to be tested, only three terminal ones.

thanks a lot. I tested some of them and found it's like vcc and ground are short. So there are many possibilities for different components failing. I just found a cheap zsus board on ebay $17 so I bought it to make it faster. Thank you again, I hope by replacing the zsus board my TV could come back

[tom66]

Re: LG 50PZ550 / Zenith Z50PV220 clicking not power on, troubleshot but not sure

I often do that, I have found Z-sustain (or X-main) for as little as £12, I just replace the board, not worth putting in a £10 Farnell parts order when there could be more wrong. Hopefully it fixes your TV.

[AngusY1]

Re: LG 50PZ550 / Zenith Z50PV220 clicking not power on, troubleshot but not sure

Hi. I have almost the same problem with my Zenith z50pv220 tv. when I want to turn it on, just clinking and it goes bact to standby. No picture and sound it does not turn on. I bought a new z sustain and a new power supply but the problem is stayed. Somebody has any idea what can I do? Thank you