Hi, I have a ViewSonic UltraBrite A90f+. The problem is that when I use it the screen will fade quickly and then stay black.

The green indicator LED says on never switching to orange (no signal/auto off).

When I press the configuration buttons on the monitor none of the menus appear.

I've tried turning it off, waiting a minute, then turning it back on. But the screen just stays black. With the green LED on.

The only way I can start using the monitor again is if I turn it off and let it sit for about and hour or two.

I am using a APC UPS so I dont think it got fried or anything. All my other hardware is fine.

BTW I do have all powersave/screensaver funtions turned off.

I have 3 computers and this monitor has the same problems with all three.

Sometimes I get lucky and am able to use the computer for an hour to and hour and a half, but most times it is 20 to 40 minutes.

This is a fairly new monitor, I only purchased it in January 03.

Any ideas on whats wrong with it? Does it sound fixable?

Hi does the picture go away instantly or fade over 15 to 30 seconds. If it fades then check the heater supply if it just goes away then I guess it is being blanked because the micro thinks there is or sees a fault.

Rich

Its sort of just POOFs. It image looks like its zooming in as it fades out. The whole thing takes about 2 to 3 seconds.


I have never taken any courses on monitor repair and I know nothing about it. So a description of anything you might think is wrong would be greatly appretiated. Also if you could give me an idea of how much any repair you think it needs cost would be great.

Also do you think I should get in contact with the manufacturer?

Hi this is the EHT shutting down this may be due to the EHT being to high and very close to the over voltage setting. The cause can be either a capacitor going low in value or a resistor changing value the problem being that this resistor can be inside the EHT transformer.

Cost will depend on the experience of the engineer on that model and monitor repairs in general and the component(s) causing the fault £30 to £100.

If I did not have the test equipment needed I would if it was mine measure a voltage supplied by the EHT transformer and turn down the HV pot about 5% and try it if this stopped it switching off I would use it until it started to happen again.

Rich

If it is in warranty then any attempt by you to fix it will invalidate that warranty.

Contact the manufacturer.

Did u measure the dc voltage of the heater when it goes blank.If there is no voltage,trace it to the tansformer that is supplying the voltage.Probably dry joints.

wow, i really have no idea of how to measure anything. ive never even seen a monitor with its case off.

What sort of things would cause the monitor to act this way?

If it is the EHT or dry joints, what would cause those problems? Does it sound like a defect that was present when I bought it and just took a little time to start affecting how it functions?

If you dont work on Monitors/tvs,, Be VERY careful about poking around inside 1,, Their are X-TREMLY high voltages present inside these units! 27,500 @ an average to the anode of the crt<picture tube>,, The big red rubber boot and wire leading to the top of the glass from your flyback transformer... Please find som1 that does this regularly.. Hate to see you get it.. (has happened to me be4,SNAP!!)..in my younger days.. Good luck on your fix!! Richard is right.. probably cold/dry solder joints.. But if you dont do this. you can actually cause more harm than good. Have a good 1!! Ken

I have a Gateway 2000 EV900 7000595 with basically the same problem. It works perfect for 8 minutes then turns off but the green light stays on. It has to be turned off for a while to work again. I was wondering if it might have the same thing wrong with it. Thanks

Matt

Maybe as a lot of Gateways are LG monitors and suffered from FBT failure.

Rich

This sounds to me like it could just be a bad soldier joint on the DC side.

Mine did the same thing so I looked at my pins and found one of them crooked. When I straightened it back out, it worked, but the picture was distorted. The middle was oblong and the top & bottom was scrunched up.

I have 2 Viewsonic one is A90F another A90F+ Ultrabrite. Both have the same issue you are having. And you know the best part is, I sent it to repair they both sent back to me still broken. Viewsonic suck, makes lemon monitors and have bad service but thats just my experience. Forgive my bitterness but its so annoying when u are working and all of the sudden everything goes black on ur screen. I really thought Viewsonic is a trustworthy company i guess i was wrong.

Anyway, since im out of warranty, Im left to one option to fix it myself. So if anyone would drop me a few line where are those soldiers inside, id give it a try. I did take it apart before and im pretty handy, i build a few computers before.

... thanks for any help anyone can provide.



Las