Attempting to repair a Dell 2208WFPt monitor without a clue

[max.wwwang]

Hi there, Help wanted.

I have a Dell 2208WFPt monitor which is not working properly. It powers on and displays as it should but only for a few seconds then turns to black (looks like power-saving mode). The OSD menu button does not respond. I searched extensively online; it appears a common problem of this model on the Dell community website such as this: https://www.dell.com/community/Monitors/2208WFP-not-working/td-p/2826526. The Dell community website does not seem to give a solution except perhaps a replacement of the whole thing for some users whose complaint is the loudest. There are YouTube videos about replacing the bulging (visibly failed) capacitors which do not apply to my case (my caps are in perfect visual condition).

I tested it on two computers with different cables (both from VGA and DVI, all converting to HDMI or DP).

Wondering if anyone here happens to have experience of this and got a solution or a clue.

[MikeK]

I recently fixed a trash-find 22" HP monitor.  Similar problem...The display wouldn't stay on.  It turned out to be bad solder joints at the CCFL bulbs.  It's worth checking, as it doesn't require any special tools or skills.  By the way, the menu button may not respond if there is no display input signal.

[tunk]

There are YouTube videos about replacing the bulging (visibly failed) capacitors which do not apply to my case (my caps are in perfect visual condition).

Even if they look OK, they may still be bad.

[wraper]

Most likely CCFL inverter going into protection and thus backlight shutting down. The most common reasons are bad electrolytic capacitors (usually bulge on the top but not always), bad CCFL transformer secondary winding or bad lamp.

[wraper]

By the looks of PCB, CCFL transformer should have 2 secondary windings. Measure their resistance, it should be about 1 kOhm and almost identical for both windings. If winding measures open or winding resistances have significant difference then transformer is bad. EDIT: I think it's probably a wrong picture of power PCB on ebay or there are 2 versions of it. Another picture has 2 smaller transformers which should have a single secondary winding. In either case suggestion about measurement remains the same.

[FIXITNOW2003]

not seen the 22" version but had a 2408WFP going into standby randomly needed to replace
 1x 150u/450V
 5x 470u/35V
 2x 47u/50V
 1x 1u/100V

[max.wwwang]

I recently fixed a trash-find 22" HP monitor.  Similar problem...The display wouldn't stay on.  It turned out to be bad solder joints at the CCFL bulbs.  It's worth checking, as it doesn't require any special tools or skills.  By the way, the menu button may not respond if there is no display input signal.

Thanks. Have brought the monitor back together after the post and it has been collecting dust. Might get another crack on it before giving up - it's a bit hassle to crack the case open. 

[max.wwwang]

Even if they look OK, they may still be bad.

That's very true. But as an inexperienced repairer, I would exhaust all other tricks before replacing good-looking caps. Thanks.

[max.wwwang]

By the looks of PCB, CCFL transformer should have 2 secondary windings. Measure their resistance, it should be about 1 kOhm and almost identical for both windings. If winding measures open or winding resistances have significant difference then transformer is bad. EDIT: I think it's probably a wrong picture of power PCB on ebay or there are 2 versions of it. Another picture has 2 smaller transformers which should have a single secondary winding. In either case suggestion about measurement remains the same.

Thanks. Will post a picture of the board if I got time to have another try.

[max.wwwang]

Hi there! It sounds like you have already tried many different things to troubleshoot this issue. Have you tried contacting Dell support? They may be able to help you mend the issue or provide a replacement monitor. It's possible that the problem could be with the monitor itself or with the cables you're using. Have you tried testing it with different cables or with a different monitor? You can also find more support and Monitor Tips at guys from  MonitorPlex . I hope you can get the problem sorted out soon.

Yes, indeed I have tried many things and have done extensive, if not exhaustive, search online without much useful information for this particular case. I don't believe Dell will help me as I'm not the original owner and it's very old. I've also considered the possibility of the cable issue so checked with a couple of different cables, known to be working on other monitors, but without luck. Thank you.

[max.wwwang]

not seen the 22" version but had a 2408WFP going into standby randomly needed to replace
 1x 150u/450V
 5x 470u/35V
 2x 47u/50V
 1x 1u/100V

Thank you for sharing your experience. The problem of your 24" one sounds like different from my 22" - this one does not go into standby randomly, but rather in a predictable and repeatable way. That is, going into standby a few seconds after switched on. Before going off, it works like normal. Then never comes back. Despite of this difference, I will look more closely at the caps you mentioned if I got the chance to crack its case open again and give it another try.

[max.wwwang]

Actually I did take these photos then I opened it last time.

[max.wwwang]

And this one.