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Old 09-07-2010, 09:27 AM   #21
retiredcaps
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Default Re: Viewsonic VA1912wb problems

The voltages look good to me.

Maybe it is time to carefully reseat the cables from the logic card to the panel. If you can, reseat the connector to the panel and the connector to the logic card.
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Old 09-07-2010, 09:55 AM   #22
justin_otherguy
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Default Re: Viewsonic VA1912wb problems

Quote:
Originally Posted by retiredcaps View Post
The voltages look good to me.

Maybe it is time to carefully reseat the cables from the logic card to the panel. If you can, reseat the connector to the panel and the connector to the logic card.
I was able to reseat the 3 ribbon cables to the logic board. This produced no change in the symptom.

I keep going back to the fact that this was not my original problem. It was a screen flicker only. The only thing I changed originally was 2 caps. The flicker was fixed but then the "negative" image reared its ugly head. Since then, nothing I've done has had any change.

To my thinking, 2 things are possible.
1) I somehow screwed something up on the power board with my iron. And I have looked and looked with a magnifying glass for solder bridges and such.

2) Coincidentally, something on the logic board fried. Maybe as a result of my actions, maybe not.

I just wonder if this problem could be caused by what I did on the power board since the voltages going to the logic board look okay.

Frustrating to say the least.
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Old 09-07-2010, 10:21 AM   #23
retiredcaps
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Default Re: Viewsonic VA1912wb problems

So just to confirm, you tried (on the buttons)

1 + down arrow + up arrow

to reset the white balance?

If that doesn't work, did you try a restore factory defaults?

If that doesn't work, try a bios update on the monitor? That might overwrite something that is corrupt in the firmware and restore the picture back to normal.

All this is from

http://ftpkuban.com/FTP/Manual/ViewS...W_Wb_SM_1a.pdf
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Old 09-07-2010, 11:17 AM   #24
justin_otherguy
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Default Re: Viewsonic VA1912wb problems

Quote:
Originally Posted by retiredcaps View Post
So just to confirm, you tried (on the buttons)

1 + down arrow + up arrow

to reset the white balance?

If that doesn't work, did you try a restore factory defaults?

If that doesn't work, try a bios update on the monitor? That might overwrite something that is corrupt in the firmware and restore the picture back to normal.

All this is from

http://ftpkuban.com/FTP/Manual/ViewS...W_Wb_SM_1a.pdf

I'm not sure what is supposed to happen with the white balance. I press the keys, no menu, no change in screen.

Factory defaults - I assume you are talking about the one in the regular menu, that has no effect also. The manual really lacks some details.

Firmware update: I was able to find the MStar app. I haven't actually tried to find the correct firmware yet because I don't know if there is anyway to even do the update without that hardware that looks like it plugs into a parallel port and the monitor.
Any experience with that?
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Old 09-07-2010, 12:36 PM   #25
retiredcaps
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Default Re: Viewsonic VA1912wb problems

Quote:
Originally Posted by justin_otherguy View Post
I'm not sure what is supposed to happen with the white balance. I press the keys, no menu, no change in screen.
On my Viewsonic VX922, if I press 1 (hold it down), then down arrow (hold it down - so now buttons are held down) and finally up arrow, it blinks "white balance" on mine.

1 + down arrow + up arrow is like pressing Ctrl-Alt-Delete. All 3 have to be held down.
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Old 09-07-2010, 12:50 PM   #26
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Default Re: Viewsonic VA1912wb problems

Works on my VX2235WM as well
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Old 09-07-2010, 12:54 PM   #27
jetadm123
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Default Re: Viewsonic VA1912wb problems

One additional thing you might check are the voltage regulators on the logic board. I think they are U4 and U6. You'll need to verify the part numbers, but I think they are LM1117-XX where XX is 18 or 33. If yes, and going by your original photo, then from left to right are pins 1-3. Pin 4 is the large soldered tab at the top. According to the datasheet:

pin 1 = ground
pins 2 and 4 are connected = voltage output
pin 3 - voltage input (5v)

Also, there's a Q8 next to U4. Can you read off the part number?

Last edited by jetadm123; 09-07-2010 at 12:57 PM..
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Old 09-07-2010, 02:56 PM   #28
justin_otherguy
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Default Re: Viewsonic VA1912wb problems

Quote:
Originally Posted by retiredcaps View Post
On my Viewsonic VX922, if I press 1 (hold it down), then down arrow (hold it down - so now buttons are held down) and finally up arrow, it blinks "white balance" on mine.

1 + down arrow + up arrow is like pressing Ctrl-Alt-Delete. All 3 have to be held down.
I was able to see a box pop up, but I think because of my strange screen colors, cannot read it. Pic attached. The little slider does move from left to right, but I don't seem to have any control over it, and it doesn't change anything that I can see.

Quote:
Originally Posted by jetadm123 View Post
One additional thing you might check are the voltage regulators on the logic board. I think they are U4 and U6. You'll need to verify the part numbers, but I think they are LM1117-XX where XX is 18 or 33. If yes, and going by your original photo, then from left to right are pins 1-3. Pin 4 is the large soldered tab at the top. According to the datasheet:

pin 1 = ground
pins 2 and 4 are connected = voltage output
pin 3 - voltage input (5v)

Also, there's a Q8 next to U4. Can you read off the part number?
Okay, more pictures attached.

U4 & U6 = AMC1117 -3.3 F0550J
Q8 = ZCPn
Attached Images
File Type: jpg WB_screenfull.JPG (1.67 MB, 49 views)
File Type: jpg WB_screencloseup.JPG (1.16 MB, 41 views)
File Type: jpg U6.JPG (992.6 KB, 37 views)
File Type: jpg U6Q8.JPG (1.38 MB, 40 views)
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Old 09-07-2010, 03:15 PM   #29
jetadm123
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Default Re: Viewsonic VA1912wb problems

Looks like U4 and U6 are putting out the required 3.3V.
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Old 09-07-2010, 10:18 PM   #30
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Default Re: Viewsonic VA1912wb problems

Quote:
Originally Posted by retiredcaps View Post
On my Viewsonic VX922, if I press 1 (hold it down), then down arrow (hold it down - so now buttons are held down) and finally up arrow, it blinks "white balance" on mine..
Is there a factory reset key sequence that he can try "blind"?
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36 Monitors, 3 TVs, 4 Laptops, 1 motherboard, 1 Printer, 1 iMac, 2 hard drive docks and one IP Phone repaired so far....
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Old 09-07-2010, 11:55 PM   #31
retiredcaps
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Default Re: Viewsonic VA1912wb problems

Quote:
Originally Posted by jetadm123 View Post
Looks like U4 and U6 are putting out the required 3.3V.
Actually, was U4 and U6 actually tested by the OP? I don't see the measurements anywhere?
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Old 09-08-2010, 05:38 AM   #32
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Default Re: Viewsonic VA1912wb problems

Quote:
Originally Posted by retiredcaps View Post
Actually, was U4 and U6 actually tested by the OP? I don't see the measurements anywhere?
The voltages are on my latest pics... #28
I wasn't real sure of the pin numbers, so I just made it visual.
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Old 09-08-2010, 06:39 AM   #33
jetadm123
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Default Re: Viewsonic VA1912wb problems

Q8 on the logic board is a ZCPn is a manufacturer marking. Does anyone know what the actual part number is?

Last edited by jetadm123; 09-08-2010 at 06:44 AM..
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Old 09-08-2010, 01:51 PM   #34
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Default Re: Viewsonic VA1912wb problems

That really is a weird problem.

The only thing I can think of is that you somehow introduced static electricity to the eeproms on the main board and corrupted the values stored inside.

I can't remember if you can modify those values...
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Old 09-08-2010, 01:56 PM   #35
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Default Re: Viewsonic VA1912wb problems

Quote:
Originally Posted by justin_otherguy View Post
I was able to see a box pop up, but I think because of my strange screen colors, cannot read it. Pic attached. The little slider does move from left to right, but I don't seem to have any control over it, and it doesn't change anything that I can see.
I don't think you did this right. That slider (I might be wrong), is for OSD lock or Power lock.

It should have a rectangular box with red gree blue (like a flag) and the screen colour should change as the set try to adjust the white balance. You also should have a colour bar pattern on the screen so you don't have the white balance set wrong/skewed.
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Old 09-08-2010, 07:40 PM   #36
justin_otherguy
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Default Re: Viewsonic VA1912wb problems

I have tried to get the white balance menu to come up repeatedly, to no avail.
I did narrow down how I got the one show in the attached pic.

I can only seem to get the main menu [1], acontrast/brightness [^] or [v], reset brightness [^]+[v], and the one in the pic... [1] + [^] or [1] + [v], [2] will toggle between DVI and Dsub inputs. And the speakers will mute.

It's just become Bizarro Monitor!
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Old 09-10-2010, 09:07 AM   #37
lucky13
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Default Re: Viewsonic VA1912wb problems

justin_otherguy,

Because you have to press 3 buttons TOGETHER at he same time, it is difficult and takes many tries.

I suggest you place your monitor flat on the desk, face up. This way you can time and press all 3 buttons at the same time. Your fingers should feel the buttons being pressed at the same time.

What you are saying sounds like you managed to press 1 of the button just millisecond ahead.

BTW, if you did this right, nothing will appear to be changed for a second or two (i.e., no OSD MENU pops up), then the white balance logo kicks in.

Keep trying.....
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Old 07-10-2011, 09:14 PM   #38
ubotts
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Default Re: Viewsonic VA1912wb problems

Hi from newb could anyone pls. give me the p/n`s at DigiKey for all caps on that board thanks in advance if someone does
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Old 07-10-2011, 09:45 PM   #39
ubotts
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Default Re: Viewsonic VA1912wb problems

Hi from newb could any one pls. give me the p/n`s at DigiKey for all the caps on that powerboard or all their values thanks in advance
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