Dell 2407WFPb backlight work, LCD doesn't

[funkster]

Hello and firstly thanks for everyone who has helped me in the past to fix my Chimei 221D, it's still going strong till this day .

Today my problem is with my Dell 2407WFPb, initially it was working with just a minor problem with a 1 pixel vertical line stuck on the far left, it didn't bother me much at first, but after a few months it did. So I did something stupid and opened it up and while powered on tried to see if the tab bond was the problem, it didn't seem like a tab bond problem as I tried to press it down so I decided to put it back together and let it be. The problem occured when the LCD slipped out of my hands while powered and I heard a small zap sound. Ever since that happened the actual LCD would not display, the backlight works and the Monitor turns on. Is it possible that I blew a tiny fuse? I have attached some photos of the circuit boards that may have the issue, I will take some more photos of the other circuit boards if needed.

Cheers,

funkster

[Mr Bill]

Re: Dell 2407WFPb backlight work, LCD doesn't

Check this fuse and see if it's blown.

[funkster]

Re: Dell 2407WFPb backlight work, LCD doesn't

Hmm, I just checked the fuse. It shows roughly 79 ohms on my multimeter. Thanks for helping by the way.

[selldoor]

Re: Dell 2407WFPb backlight work, LCD doesn't

Suggests it is blown - what does your meter say when you touch the
probes together. Remove the fuse or lift one end and retest.

[funkster]

Re: Dell 2407WFPb backlight work, LCD doesn't

When i touch the probes together my meter reads 1 ohm, I desoldered the fuse and it's the same 79 ohms.

edit: I tried a temp fuse and it worked. Though the picture is having more issues than before, there is a large horiztonal band across the middle, it splits the picture like it draws what is meant to be the next row, but moves it down if you get what I mean, and the bottom part is not displayed and cut off. The original 1 pixel line on the left remains as it first was. I have uploaded a photo.

[funkster]

Re: Dell 2407WFPb backlight work, LCD doesn't

I found what is causing the horizontal banding issue, it's the middle tab bond, when I press it down it fixes the issue. Perhaps if I put some tape on top and place the metal case it will hold it down. The 1 pixel line remains though.

[selldoor]

Re: Dell 2407WFPb backlight work, LCD doesn't

I have read that some people have had some success with packing between panel and frame. Also heating with a hairdryer then pressing until it cools has had some success but you could make it worse - I have not tried either of these myself. The red line could be on another part of the bond?

[funkster]

Re: Dell 2407WFPb backlight work, LCD doesn't

Unfortunately I couldn't fix the tab bond, it's beyond repair. I tried many times different thicknesses of tape and it always failed and to the point of me not even being able getting the tab bond working even by holding it down with my finger. Oh well I'll keep this monitor for spare parts as my brother has the same monitor. Thanks for your help selldoor.