HP W2207 Backlight Problem

[TVo]

Re: HP W2207 Backlight Problem

Bah, I had meant to attach a photo of the back. I think it error'd out last time.

Here's a back photo.

[jetadm123]

Re: HP W2207 Backlight Problem

Looking at your photo, it looks like each inverter transformer has two pins (marked 7 and 8) on their secondaries, which feed a pair of ccfl's. Can't tell if there are more pins on the secondaries (which is why we usually ask for a photo of the bottom of the board). Assuming 2 pins and with power off and your meter set to resistance, measure across pins 7 and 8 of each inverter. If the difference is greater than 3%, then you may have a problem.

[TVo]

Re: HP W2207 Backlight Problem

They are Su'scon... Damn, I really wish I had an ESR meter. Can't justify it quite yet. I'll take that into consideration, after I've had a go at testing the transformer, just to check. What about that big fatty Cap? Are those readily available?

[Scenic]

Re: HP W2207 Backlight Problem

no help from me on the transformers, but the caps in the first few pics look like Su'scon.. replace on sight in my book..

[TVo]

Re: HP W2207 Backlight Problem

Well, bad news.

After replacing the CCFLs, I still have the same 2 seconds to black problem. I would like to test the transformers, but I'm honestly not sure which parts are the transformers and which pins I need to test.

Any advice on how to test this particular monitor's transformer? I read up on the post about the basics to do to test 2 seconds to black, but I didn't get quite enough info to test the transformers. (this post: https://www.badcaps.net/forum/showthread.php?t=10419 )

Any help is greatly appreciated!

[TVo]

Re: HP W2207 Backlight Problem

Thanks again very much for the info. I plan on writing out a guide for each of these particular models for people like me who had no idea where to start when fixing these things.

I ordered some CCFLs and they will be here in about 10 days. I plan on testing the inverter transformers as well and see if there are other issues there.

I'll post back when I for sure find out what the problem was, and I'll post a link to my guide which will hopefully have very neat pictures and a disassembly (since when I looked there were NONE for this particular model, and it was a huge pain figuring out how to get off the backplate.)

Thanks again for help, and I'll report back when it's workin!

[retiredcaps]

Re: HP W2207 Backlight Problem

Damn, you guys are fast!

Apparently not fast enough. There are a number of very good people here who participate on a daily basis.

BTW, it wouldn't hurt to check your inverter transformers to make sure they are okay since everything is apart.
Sometimes 2 seconds to black is not just due to one bad component. It could be multiple problems.

[retiredcaps]

Re: HP W2207 Backlight Problem

Should I start a new thread for an individual monitor I'm having problems with if I'm unable to diagnose from that post?

A new thread for each monitor to make it easier to follow and keep track of.

If you are able to fix the monitors without our help, it would help others if you posted a post mortem or case study writeup with pictures of the fixed boards.

[retiredcaps]

Re: HP W2207 Backlight Problem

I was checking out ccflwarehouse.com but I have no clue what type of CCFL to look for.

Phone them. Members here say they are very helpful over the phone for these types of questions.

[TVo]

Re: HP W2207 Backlight Problem

...

https://www.badcaps.net/forum/showthread.php?t=10419

Have a read through it and feel free to ask questions regarding the test procedures.

....

Thanks for that link! I have about 7 monitors (no joke) that need fixin. I'll start there. Should I start a new thread for an individual monitor I'm having problems with if I'm unable to diagnose from that post?

[TVo]

Re: HP W2207 Backlight Problem

Damn, you guys are fast!

I was checking out ccflwarehouse.com but I have no clue what type of CCFL to look for. Do I look on the old CCFLs for a part number or do I just guestimate?

[retiredcaps]

Re: HP W2207 Backlight Problem

I have a W2207 that turns on for a bout 2 seconds then the backlight goes blank. I can still see the picture on the display, but it's without any light behind it.

2 seconds to black can be

a) bad caps
b) bad inverter transformer
c) bad ccfls
d) bad ccfl wiring

All the above is explained in more detail starting with post #13 at

https://www.badcaps.net/forum/showthread.php?t=10419

Have a read through it and feel free to ask questions regarding the test procedures.

edit: Darn, I type too slow. Good job in figuring out it was c).

[alexanna]

Re: HP W2207 Backlight Problem

Darn you beat me to it.
Al


I like ccflwarehouse.But there are others.
Al

[TVo]

Re: HP W2207 Backlight Problem

If you look at my almost immediate update, you should see that there indeed was a bad CCFL! I am considering replacing all of them, as there is some black on the non-broken ones too.

Where is the best place to get replacement CCFLs?

[alexanna]

Re: HP W2207 Backlight Problem

The very first thing I would suspect in this monitor,Would be a ccfl wiring issue.
Do you have a known good ccfl you could substitute for testing?
Al.

[TVo]

Re: HP W2207 Backlight Problem

Well, as I was getting pictures of the backlights in case they could be an issue, I found a broken CCFL! I don't know if it broke when I was removing it or if it was the cause the entire time, but I think that could be my issue!

I have attached pictures of all the CCFL ends because there is a little bit of black on them. I have no idea if that means they are bad or if that's just how they are. I'll let you guys see it.

Where is the best place to get replacement CCFLs for LCDs?

Thanks!

[TVo]

Hello!

I have a W2207 that turns on for a bout 2 seconds then the backlight goes blank. I can still see the picture on the display, but it's without any light behind it.

I have taken the board apart and have attached pictures. It doesn't look like any caps are bad, but I could be wrong. I have a feeling that it's the inverter, but I don't know how to pinpoint this.

Disclaimer: I'm a bit of a noob when it comes to this type of repair, but I would really like to learn how. I may not know the proper vocabulary for a particular testing method, but I'm willing to do whatever I can to get this figured out. I have a lot of patience, so I hope I don't annoy anyone too much if I don't know what you're talking about if you tell me to try something.

Without further ado, please feast your eyes upon my boards. Thanks in advance for any help!

(The PowerBoard Back picture will not upload for some reason. I'll try a new picture later)