Hyvision by Megavision MV220 LCD monitor goes blank after 0.5-1 second

[selldoor]

Re: Hyvision by Megavision MV220 LCD monitor goes blank after 0.5-1 second

Tubes also available from ccflwarehouse.com - They have instruction videos and
members have said they are helpful with unusual sizes. Also have a ebay outlet that sometimes has bargains http://stores.ebay.com/ccfl-warehous...p2047675.l2563

[bobioni]

Re: Hyvision by Megavision MV220 LCD monitor goes blank after 0.5-1 second

Thanks for the CCFL sources. After reaching the CCFL lamps during the dis-assembly process, I discovered 2 of 4 lamps to be cracked, one partially cracked, and the last to be badly blackened (indicating end of life?) at the end of the CCFL. I'm assuming that the blackened lamp was the lamp coming on for the 2 seconds prior to going black. I'll inform after new lamp installation while I anxiously await the lamps arrival.

[bobioni]

Re: Hyvision by Megavision MV220 LCD monitor goes blank after 0.5-1 second

I installed all 4 lamps today & much to my shock & disappointment, "2 seconds to black" still exists. As stated previously, the inverter board was replaced with a known-working inverter board & just to confirm, when holding a flashlight up to the black screen, The Windows log in screen can be seen as well as the mouse pointer moving around the desktop. Firstly, I am completely perplexed as to what it could possibly be & secondly, what could have caused the old lamps to have cracked?

[stj]

Re: Hyvision by Megavision MV220 LCD monitor goes blank after 0.5-1 second

maybe the psu?
the invertor and tubes use more power than everything else combined!

[bobioni]

Re: Hyvision by Megavision MV220 LCD monitor goes blank after 0.5-1 second

Being the knowledge seeker that I am, is there a definitive way to test the PSU? The "power on" indicator light illuminates as per normal. If the PSU was faulty, would it continue to illuminate the "power on" indicator?

[stj]

Re: Hyvision by Megavision MV220 LCD monitor goes blank after 0.5-1 second

it could.
you could lose the 12/24v for the invertor but still have the 5v or 3.3v running.

you should let the invertor cutout, then meter the power on it's connector.

[bobioni]

Re: Hyvision by Megavision MV220 LCD monitor goes blank after 0.5-1 second

stj: Being the knowledge seeker that I am, when you say "you should let the inverter cutout, then meter the power on it's connector", what is meant by "let the inverter cutout"? Do you mean disconnect the inverter's incoming power supply connector and check the voltage with a voltmeter at its incoming power connector? If so, there are 8 pins on the male inverter board connector. Which of the female connector sockets will I be checking with the voltmeter? I'm a novice with respect to voltmeter usage, so being as specific as possible with voltmeter dial settings and placement of probes would be greatly appreciated. Please see enclosed picture.

[bobioni]

Re: Hyvision by Megavision MV220 LCD monitor goes blank after 0.5-1 second

I'm not certain if it's worth mentioning, but I will anyway. While reviewing the "guide on how to troubleshoot 2 seconds to black", it mentions that the "power on" LED stays lit and you can still see the image by shining a flashlight on it. This is true of my monitor, except my "power on" LED stays lit but is rhythmically flashing. Is this normal or should it be lit solid rather than flashing?

The "guide on how to troubleshoot 2 seconds to black" also mentions that for now, we will assume that the power board and logic board are working 100%. That leaves the inverter board to check. What are the power board and logic board?

[stj]

Re: Hyvision by Megavision MV220 LCD monitor goes blank after 0.5-1 second

flashing led is not normal.
it could be the psu cycling or the mainboard indicating an error

[selldoor]

Re: Hyvision by Megavision MV220 LCD monitor goes blank after 0.5-1 second

Can you post good clear pictures of the other boards front and back and close ups of the connectors showing and board menus eg 12v 5v pson This will also give you the opportunity of making sure everything is connected