2 dead monitors, blueh h94w and amw x1700ds

[retiredcaps]

Re: 2 dead monitors, blueh h94w and amw x1700ds

My symptoms are that the screen operates fine for ten minutes, then flickers and i lose the backlight, after a while presumably whilst something cools down a bit comes back on but flickers and goes out again over and again.

Most monitors from the factory are set to 90 brightness and a high contrast number. If you lower the brightness and contrast to say 40/40, does the display stay on longer?

I have a Benq with the same symptoms. By swapping parts, I determined something is wrong with the ccfls. If I lower the brightness/contrast as above, it stays on for hours. Otherwise, at factory defaults of 90/75, it goes off in 20 minutes.

[Stagdriver]

Re: 2 dead monitors, blueh h94w and amw x1700ds

Yes tried setting the contrast and brightness to a lower setting and the problem takes longer to occur.
i'm showing my ignorance but what are ccfls ?
stagdriver

[retiredcaps]

Re: 2 dead monitors, blueh h94w and amw x1700ds

i'm showing my ignorance but what are ccfls ?

http://en.wikipedia.org/wiki/Cold_cathode

You can find replacements, if that is the real problem, at

http://www.ccflwarehouse.com/

http://www.ccflwarehouse.com/lasotu.html

[arfgh]

Re: 2 dead monitors, blueh h94w and amw x1700ds

i have the same hyundai monitor with the same symptoms.
So did someone get a solution for the problem ?
i have no idea where could be the faulty component.

[selldoor]

Re: 2 dead monitors, blueh h94w and amw x1700ds

It is no good saying you have a monitor with the same symptoms - please tell us exactly what is wrong with your monitor. Tell us what happens when from when you switch it on until it reaches a stable faulty stage- advise any sounds and what is the power light doing.
Welcome to the forum-
We can help a lot more if you please post good clear pictures of the whole chassis, and then pictures of each board, front and back and close up of connectors, (max resolution 2000x2000 and 2MB) using the manage attachments button, which is found by clicking "go advanced" under quick reply.

Please do not post inline and offsite as they slow down the loading of pages.

Examples of what is needed
https://www.badcaps.net/forum/attach...1&d=1290283049

https://www.badcaps.net/forum/attach...7&d=1280167246

It will be useful if you can say what the supposed fault was and a bit about yourself - skills tools etc.

[arfgh]

Re: 2 dead monitors, blueh h94w and amw x1700ds

well it is the same monitor that the others speak in this topic.

[Rtech]

Re: 2 dead monitors, blueh h94w and amw x1700ds

You really need a set of test backlights,so you can quickly identify if the originals are the cause of your problem.The test ones do not have to be from the same model, eg a pair of 17" or 19" would be adequate for testing purposes only.

[arfgh]

Re: 2 dead monitors, blueh h94w and amw x1700ds

but the back lights works in fact, cause the image appears each certain minutes.
Then the screen blinks and the image is off

[Rtech]

Re: 2 dead monitors, blueh h94w and amw x1700ds

If it switches off even after minutes, it is still possible that the Backlights may be faulty.The other thing you can do is resolder from the inverter transformers through to the lamp sockets on the Board, as it may be a poor joint.

[arfgh]

Re: 2 dead monitors, blueh h94w and amw x1700ds

i have tested the follow. Extracted the main lcd cable, the big and flat one. And having connected the lamps with their 4 connectors. The backlight of course is on when power on, and i have waited to see if the lamps get off, but this dont happends.
Will test this more because if the lamps dont get off, they are not the problem.

What you think about ?

[Rtech]

Re: 2 dead monitors, blueh h94w and amw x1700ds

Disconnecting the cable to the screen, normally does not have any effect on the backlights, as the Backlight ON signal comes from the Logic Board, when it detects an input signal.So what you are implying is that the 'image' goes off after a few minutes BUT the Backlights stay on ??????what happens to the Power LED when the signal goes ???EG. Power on Led On, PC signal applied LED changes colour,Image goes what happens to the LED colour ???

[arfgh]

Re: 2 dead monitors, blueh h94w and amw x1700ds

well, i dont know which is the problem with this blueh monitor, but i think that comes from the video processing chip in the little board. It runs extremelly hot and i think that the same perform a cut to protect itself.

Probably exist no a fix for this without to change this little board.

What you think about ?

[selldoor]

Re: 2 dead monitors, blueh h94w and amw x1700ds

I think about if you dont answer our questions we cant help you.

[arfgh]

Re: 2 dead monitors, blueh h94w and amw x1700ds

i have change the two lights by a 17" monitor, and the same problem happends but with more time working. Also i have installed a cooler in the video processing chip, but the temperature reach high values.

So in my opinion this is the problem, this chip cant handle the temperature and cut off the lights to preserve itself.

[Stagdriver]

Re: 2 dead monitors, blueh h94w and amw x1700ds

I was the original post of this problem (stagdriver), only just been able to retrieve my log on password from PC disk that was involved in workshop fire so sorry for not responding so long. Unfortunately the monitor was also destroyed in the fire so i never got to solve the problem and post the results. Thanks for your efforts though chaps.

[flosers]

Re: 2 dead monitors, blueh h94w and amw x1700ds

Hi
I have the same problem with my H94w monitor.The first time when I power on he stay on few minutes and the screen goes black. If I try to turn on again the monitor stay 1 second on and turn off but the led steal green.I have done few test:
1.I have inspected the PSU board and all caps seem to be good,no component seem to be burn.
2.With an inverter of an annother monitor I test the 4 CCFL one by one, during 5minutes and they still on so I gess they are good.
3.I test turn my monitor on with CCFl alimented by the other inverter and the monitor still on so I have deduce that the problem come from the inverter. But I don't know what can I do for find the bad component.
I read this article: https://www.badcaps.net/forum/showthread.php?t=10419
I try to record ohm between input and output of the both transformer and they are nothing (multimeter said:1)
A pic of the PSU board: http://hpics.li/08ee9d8
Thank's in advance
(I'm french sorry for my English)

[budm]

Re: 2 dead monitors, blueh h94w and amw x1700ds

@flosers: Please post the pictures of the whole bottom side of the board and good closed up on the bottom side of the board around the inverter transformers. What are numbers as printed on top of the inverter transformers?

[selldoor]

Re: 2 dead monitors, blueh h94w and amw x1700ds

What did you have your meter set on - needs to be on ohms 2000

EDIT I have just read again the first test for the inverter transformer is the resistance
on the secondary windings. Not input to output.
No power to board
Set your meter on ohms 2000 and test S1 to S2 and S3 to S4 as in attached

Post the results in ohms.

[flosers]

Re: 2 dead monitors, blueh h94w and amw x1700ds

The two side of the board:
http://hpics.li/245a564
http://hpics.li/a1ba2ed
Transformer:
http://hpics.li/00527ac

The number on the transformer is: "SPW-099 ROHS DARFOM 20BOM 810028_ A".
I have 476 for the S1 to S2 and 485 for the S3 to S4. (Thank's for the pic she help me)
Thank's for you help

[budm]

Re: 2 dead monitors, blueh h94w and amw x1700ds

"I have 476 for the S1 to S2 and 485 for the S3 to S4. (Thank's for the pic she help me)" on both transformers? Otherwise it looks OK.