Re: Viewsonic VX2235WM-3 problems

I managed to strip it enough to get to the TCON board but I couldn't find anything there. Nothing obvious. There look to be a couple of voltage regulators on there but I could not find anything amiss.

I think I have spent more than is reasonable on this project so it is going to recycling. Thanks for the help though!

Re: Viewsonic VX2235WM-3 problems



OK, that makes sense.
I'll have to dig further into the panel to find that.
What an interesting adventure!...

Re: Viewsonic VX2235WM-3 problems

Thanks for the suggestions.
I can verify that 5V is present on the P104 connector and if I put a VGA signal on the VGA port from a PC, I can see activity on the LCD lines lines on that connector.

When I look at the panel though, I only see the backlight and no display content.

It is very strange.

My scope is very old and not really intended for looking at this kind of thing. It looks like the signals are offset by about 1.5V but oscillating by about 0.25V. Take that with a pinch of salt however since...

Re: Viewsonic VX2235WM-3 problems

I also check the reset signal on the logic board. Jumps up briefly on power, drops to ground quickly after. Cap/diodes seem good.

If people think that there is still some merit in recapping the PSU (perhaps the levels are not as stable as my old analog scope seems to think) I am happy to do that and come back to it. There is no obvious cap deterioration although of course there isn't always a physical sign.

Also, confirmed that pin 9 of the power cable bound for the main logic board, at the PSU side, is not connected. It...

Hi,
I am trying to diagnose an issue with the above monitor.
Initially, I assumed that it was a PSU issue, but I'm not so sure.
OK, here are the symptoms:

Powering on the monitor, the backlight comes on, but there is no display on the panel. The power light is illuminated Blue.
After about 3 seconds, the backlight goes off and the the power light goes Amber.
I cannot get it to do anything with the buttons with either the blue or amber lights illuminated.

If I plug in a VGA source, then the panel stays on indefinitely, blue light + backlight....

Re: Samsung SyncMaster 275T power supply

Just an update on this issue.

I too had the exact same issue as the poster with this monitor supply.
Replacing CM802 also did the trick for me. Seems to be a failure point for this PSU.