Viewsonic VX2255WMB Grey Screen

[tieny]

Re: Viewsonic VX2255WMB Grey Screen

Since jumper resistors have low resistance close to zero, wouldn't they just act like wires? In that case could I just find another jumper resistor from a salvaged circuit board and use it? How does the size of a jumper resistor affect it?

From the old resistor I took out from the video board (R22) you can see that the bottom has lost the metal part that connects the solder between the resistor and the board.

Would it be fine to use the new resistor I found from a salvaged board? Its "about" the same size and it has the same resistance of 0.4 ohms.

[momaka]

Re: Viewsonic VX2255WMB Grey Screen

VCC1: 2.51V, 457Ω
VAA:12.7V, 1336Ω
VGL: 6.9V, 712Ω
VGH: 19-20V fluxuating, 962Ω

For the fuse, I measured 5.04V going into it.

Voltages and resistances look good. The fact that you are no longer getting a white screen means the t-con should be working fine now.
...
Onto the next problem... 3 seconds to off. This would likely be a video/logic board problem. The open-circuited resistor you found could be the problem or at least part of it.

Since jumper resistors have low resistance close to zero, wouldn't they just act like wires? In that case could I just find another jumper resistor from a salvaged circuit board and use it?

Yes and yes.

How does the size of a jumper resistor affect it?

The bigger it is, the more current it can handle. On the video/logic board, however, there's hardly any high currents, so the size doesn't matter that much.

From the old resistor I took out from the video board (R22) you can see that the bottom has lost the metal part that connects the solder between the resistor and the board.

That's usually fine. As long as the top part still has the metal contacts intact, I just rotate it 180 deg. and solder it that way. Of course, this is only if you need to reuse the resistor. I would say save it for now.

Would it be fine to use the new resistor I found from a salvaged board? Its "about" the same size and it has the same resistance of 0.4 ohms.

Well, it would be fine to use the new resistor *only* if you know for sure what the resistance of the old one was. Codemonkey didn't clearly indicate what it was.
Did you try measuring it with the highest resistance setting on your multimeter (usually 2000K/2M or 20M)? Also, check the resistance of the spot where the resistance was.
Putting a jumper resistor in the spot of a resistor that could have possibly not been a jumper resistor can damage the video/logic board.

Some other questions I have:
- Did you try connecting your monitor to a computer both through DVI and VGA inputs?
- Does your computer recognize the monitor on either?
- Also, if you press any of the menu buttons on the monitor, does it turn ON then back OFF in the same manner?
- When the monitor is on, can you see a menu or OSD appear if you press any of the menu buttons?

[tieny]

Re: Viewsonic VX2255WMB Grey Screen

I'm pretty sure it was a jumper resistor. I was able to measure the old resistor after moving the probes around a bit and it gave me 0.4 ohms. Well I replaced the resistor and the monitor is working now!

But theres another problem, the monitor would keep randomly flashing black and back to my desktop and it would display the word "digital" on the top right of the screen. Any ideas?

[selldoor]

Re: Viewsonic VX2255WMB Grey Screen

You seem to be getting a bit nearer - I am still worried that you get so many readings at 0.4 ohms. -maybe thay are all just Zero Resistors. On my cheapo meter thats what I get when I touch the probes together. Can you try testing some other resistors - big ones- just to check the meter.

I dont know and it doesnt say in the handbook, but I would suggest that when it flashes Digital it is simply advising that you are using a digital input (are you?) If you use a vga input it may flash "analogue" In the handbook it indicates that if you have both Digital and Analogue inputs you can select which you want to use.

How long between black/screen flashes - perhaps it is a resolution issue.
Can you try a lower resolution, and can you get into the OSD and do a reset?

Handbook attached

[tieny]

Re: Viewsonic VX2255WMB Grey Screen

Well all of the other resistors measure 100 ohms or greater, it was just those 9 resistors that codemonkey pointed out that measured 0.4 ohms. I'm guessing he might of mistaken resistors with low resistance as being shorted?

I'll try hooking it on VGA to see if i still have the problem.

When I first plug it in and turn it on it would be fine for about 3 minutes or more, then the flashes would kick in every 15-20 seconds. What do you mean when you say OSD reset?

[selldoor]

Re: Viewsonic VX2255WMB Grey Screen

What do you mean when you say OSD reset?

OSD is On Screen Display? - you use it to adjust the screen. There is usually a button press to reset it all back to factory settings, brightness colour, contrast etc and usually puts it into native resolution.. It should be in the manual I uploaded but confess I havent read it all - just skimmed for digital

[tieny]

Re: Viewsonic VX2255WMB Grey Screen

Well i solved the problem, i noticed that it went black once it started flashing colored lines for a second so I thought it would of been the resistor I put in. I reflowed the solder for the resistor and tried turning it on again.

I think it worked, I left the monitor on for 30 minutes with no more flashes! Now its working perfectly hopefully. =)

[momaka]

Re: Viewsonic VX2255WMB Grey Screen

Nice work!
Keep us posted how it works in the long run. Would be interesting if this was indeed the problem.

I'm not entirely sure, but there was another person on craigslist here who was selling a monitor like that for $25. Might have been codemonkey himself since the location was the same. I guess I should ask him. I've been eying that monitor for a while, now. Unfortunately, the listing just expired a few days ago so I wasn't able to reply. Hopefully it gets re-listed again. Wouldn't mind giving this a shot to see if I can confirm your findings.

[tieny]

Re: Viewsonic VX2255WMB Grey Screen

Haha I actually got this monitor from craiglist in Germantown awhile ago. I was really surprised to find the same monitor on a forum that I randomly googled. I actually got two monitors but he said that a friend had given him one with the white screen. The second Monitor he gave me he said had problems like shutting off after a few seconds but I haven't seen that problem yet for some reason. (haven't put it to use that much)

As for the viewsonic, I kinda lost hope in repairing it when I saw the post of the exact monitor. I thought if it couldn't be fixed back then, how will I be able to do it since and I had no knowledge of any circuits other then from my college physics.

A problem still might be there since codemonkeys issue was never figured out. But since we found no problems with any of the parts at all, it may just of been a blown fuse and some bad solder connections.

[momaka]

Re: Viewsonic VX2255WMB Grey Screen

Haha I actually got this monitor from craiglist in Germantown awhile ago. I was really surprised to find the same monitor on a forum that I randomly googled. I actually got two monitors but he said that a friend had given him one with the white screen. The second Monitor he gave me he said had problems like shutting off after a few seconds but I haven't seen that problem yet for some reason. (haven't put it to use that much)

That's funny. Might be the same guy then . Although the posting on Craigslist was still up until a few days ago.
Did your Viewsonic come without a stand by any chance? Also, was the second monitor a 19"?
If so, it's probably the same monitor(s) I've been looking at on CL

[tieny]

Re: Viewsonic VX2255WMB Grey Screen

Yep! That's the exact same post haha. Now I just need to figure out how to get a stand for it. I'll probably try to build one.

[selldoor]

Re: Viewsonic VX2255WMB Grey Screen

Great news- hope it keeps going for you.