Re: Moved-Viewsonic VG2021m Blue flashing PLED no image
I guess this will be my final post.
Its been a few days and the monitor is working flawlessly.
I really like viewsonic products and before this one gave me
trouble it was well into its lifespan. I would have gotten away
with just the cap repair and the signal board. I ended up with a 'new'
power/inverter. I went with my repaired Pwr/invtr because it has the
superior components. Its output at the 12 and 5v rails were stronger
than the new. 11.87 / 4.93 vs 11.98 / 5.04, not allot,...
Medlock
USN Salmon 573
Last Activity: 03-17-2012, 10:26 PM
Joined: 09-02-2011
Location: West Covina Ca. relocated from Rogers park, Chicago
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Re: Moved-Viewsonic VG2021m Blue flashing PLED no image
Right I get that part, but why not use the 'sticker' part number when selling these boards rather than the PCB part number alone and then just refer in the description what monitors they may fit.
Or in this case list just one monitor with a note that it may work on many others. Thier Catalog showed upteen listings of the same PCB part number
with the same picture and different prices.
In the manufactoring of it, what your saying makes perfect sense, but at the resale level, it leads to...Leave a comment:
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Re: Moved-Viewsonic VG2021m Blue flashing PLED no image
Thanks for that info I ordered a few of them just to be sure.
So the video board arrived and the monitor is back in service.
However if by chance anyone who reads this and decides to order a signal
board, make sure you check all reference numbers not just the PCB hash
numbers.
For instance:
A190A2-A02-H-S1 Fits many different LCD models but not yours in particular.
There are other reference numbers on the board which will I dentify your
model. THis one...Leave a comment:
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Re: Moved-Viewsonic VG2021m Blue flashing PLED no image
Hiya Gang
a quick question while I wait for my board, due here today.
While working with the other power board and old signal board, (still trying to narrow down the short), I blew (or it blew) the 5 volt rail fuse on the pwr/invr pcb. I followed Alexannas link for the regulators and tried like heck to search that fuse package. I could not find it. Can you give some data on that SMD please. Its the one right off the 5v rail at the 16 pin connector marked with a 'W'.
Thanks
...Leave a comment:
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Re: Moved-Viewsonic VG2021m Blue flashing PLED no image
Morning everyone
ok today I briefly jumped U6's 3.2 volts to the EVA (thats the actual letters) pin and tada BACKLIGHTS!
So I am going to go ahead and get the board. I traced the short to the main chip on the signal PCB. I think I lost the PCB to the power annomaly we had recently, where we didn't lose power completely but we had a low voltage situation for about 2 hours. I had run around the house turning off all he surge protectors but forgot that the monitor was on a separate one all to itself....Leave a comment:
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Re: Moved-Viewsonic VG2021m Blue flashing PLED no image
Hmmmm
Well I could go that route however a few reasons will keep me from that.
1. I can jumper pin 1 and pin 4 (Ill have to verify which pin(s))
and clear it. I really dont think its that simple of a problem.
2. I have now invested 35$ in a new invt/power board, 15$ in caps,
13$ in a new chipquick set up, and couple of bucks for regulators.
The new signal board only cost 30 bucks and its local.
My fault as I started shotgunning before I came here but I really...Leave a comment:
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Re: Moved-Viewsonic VG2021m Blue flashing PLED no image
Hi Folks,
Well i tried every concievable combo of button pushing and holding with the power unplugged then holding and plugging etc etc...no change..not surprised, if it were that easy I would have contemplated shooting myself in the foot...Leave a comment:
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Re: Moved-Viewsonic VG2021m Blue flashing PLED no image
Converted from PDF tp JPG...Leave a comment:
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Re: Moved-Viewsonic VG2021m Blue flashing PLED no image
I finally found the schematics...I have seen some references to eprom reset
for other models but not for 2021.
Your submission could not be processed because a security token was missing.
could not upload them!Leave a comment:
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Re: Moved-Viewsonic VG2021m Blue flashing PLED no image
Hi Bill
Hmmm combo of buttons eh....
There are 4 buttons and a settings reset
I have tried the reset....now let me get out my abacus and determined how many combos might I need to try..ha!
Just to repeat myself...the flashing PLED comes on immediatly when plugged in,
if that makes a diff.Leave a comment:
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Re: Moved-Viewsonic VG2021m Blue flashing PLED no image
Hi Joshnz
Top row 4.98
Botom row 4.98
note:
the new regulator that i just put in U4 is showing signs of over heating.
Granted that i am using a human digital thermometer.
The U6 is at 90 and the U4 is approaching 110 and continues to climb.Leave a comment:
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Re: Moved-Viewsonic VG2021m Blue flashing PLED no image
Top Row- power plug at bottom left
- ADJ
- GND
- GND
- +5V
- +12V
- MUTE
- AOR -
- AOL-
BOTTOM ROW
- EVA
- GND
- DET
- +5V
- V_ADJ
- SHUT
- AOR+
- AOL+
I have figured that AOL-R +/- are audio
11.8 at the 12v pins are constant and are the same on both the new and repaired boards. With load and without.
No backlights what-so-ever, they do not flash...Last edited by Medlock; 09-13-2011, 12:24 PM.Leave a comment:
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Re: Moved-Viewsonic VG2021m Blue flashing PLED no image
I have not been able to find a schematic for either board.
However the pins are marked clearly, but of course abbreiviated.
I will get a picture or write these tags down.Leave a comment:
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Re: Moved-Viewsonic VG2021m Blue flashing PLED no image
Pictures done correctly...Leave a comment:
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Re: Moved-Viewsonic VG2021m Blue flashing PLED no image
Greetings Alexanna,
I have replaced the regulator and the voltages are now correct. 4.98 on the input 3.28 on the output. Voltages are steady. However nothing has changed. The PLED is still flashing has soon as the power plug in connected. No backlight, no OSD, and of course No image when hooked up to computer.
Should I not have at least back light as it seems they are powered from the invert/power board?
Is there, as in the instance of a motherboard, a signal to the power board...Leave a comment:
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Re: Moved-Viewsonic VG2021m Blue flashing PLED no image
Ok
The voltages leading from the 5v pin that feeds U4 and U6 are steady. The caps in and around problem area are of decent ohmage. Output of U6 is in spec and very steady. However U4's output as you said is out of spec and further is fluctuating irratic. +/- 1.2-.5 volts. This voltage feeds Q8 and therfore causes flucutation in its output also. This fluctuation is obviously persistent throughout all circuits supplied by these outputs. U4 does seem to be of higher temp than U6.
Question:
...Leave a comment:
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Re: Moved-Viewsonic VG2021m Blue flashing PLED no image
I noticed on the back side of the signal boards PCB a discoloration in and around the regs, due to excessive heat I would think. Funny thing is that if you look at it through plain sight it is not as noticable. I will begin the trace back and see where the drop originates.
thanksLeave a comment:
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Re: Moved-Viewsonic VG2021m Blue flashing PLED no image
i was not aware of the 'manage attachments' at the bottom of reply page...i am working on a 14" monitor and didn't scroll far enough I guess.
sorry about that.....if need be I can restart this whole thread, wow could I have messed this thread up any worse?
Leave a comment:
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Re: Moved-Viewsonic VG2021m Blue flashing PLED no image
Hi Alexanna thanks for your responce.
Pins at the 18 pin for 5v and 12v are 4.9 and 11.8 respectivly.
Fuse is good
U6 is the same as U4
U4----2.7
--------I
--I-----I-----I
-G----2.7---4.6
U6----3.2
--------I
--I-----I-----I
-G----3.2---4.9
Q8----1.4
--------I
--I-----I-----I
-G----1.4---2.7
note: on the top pins...Leave a comment:
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Re: Moved-Viewsonic VG2021m Blue flashing PLED no image
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