Inspiron 1545 LED screen - no backlight?

[SpiderBy]

Hi guys,

I have a problem and looking for your help.
Recently I broke the screen on my laptop and I have purchased and received a replacement Dell Inspiron 15.6" Matte 1600x900 LED screen from an internet retailer.
The problem is that when I connected it to the laptop first time it did not work, I figured out there was a loose connection for my flex cable (my bad), then I made the connection firm and I got my new screen working perfectly! I got happy and screwed back the screen. Before assembling everything back, just tried it again and damn - the picture became very-very dark. I mean, no colorful details on the screen - I do see a picture but it is shades of dark grey - i can hardly see something there but again, the picture is there. I don't know much about LED screens but I would say it looks like there is no "backlight" or something like that.
Note, when I switch to the external monitor - everything is fine. First I thought the culprit is the flexible LED cable that goes from the motherboard to the LED screen. I just thought that maybe I broke the cable or its connection when I was disconnecting/connecting my LED screen. I figured out the cable part number (R267J) and ordered a new one from Dell. Once it arrived, I tried it - the same problem . So right now I definitely know the following:
1. The replacement LED screen must be good cause I saw it working and it is actually showing something, just there is a lack of brightness or "backlight"
2. The LED flex cable is good (I have the old and new one - they work the same)
3. The external LCD monitor connected via VGA works well - so it looks like the video controller is OK

Guys, what should I try next?

Thank you in advance!

[kapilk007]

Can be a problem with the connector on mobo.
and btw did u got correct pictures with the led (even for once) ?
if u didn't then how could you say that the replacement LED is good...

[SpiderBy]

Thanks for the comment.

The replacement LED screen is good, my actions were as follows:
1. Connected the replacement LED screen first time with a loose connection - no picture at all (my stupidity here)
2. Connected the replacement LED screen second time with the OLD LED flexible cable and firm connection - everything was fine, bright crisp picture!
3. Assembled the replacement LED screen (screwed it to the steel brackets and to the plastic lid), connected the OLD cable again, tried - no picture, just shades of dark-dark grey and I can recognize the picture.

Whatever I tried after (including a NEW LED flex cable) - nothing worked, still the same shades of darkness.
I can even add that I have tried my OLD cracked LED screen - before I had bright light cracks, now they are also very dark.

If it is a connector on mobo, how can I be sure and what can I do with that if this is a culprit?

[Loafmanuk]

Hi, I am just wondering if you ever found a fix for this issue. I have the exact same issue, new LED backlit screen to replace a broken one. Backlight no longer works on new or broken one (did work on broken one before removal). I ordered a new ribbon cable on the advice of Dell, but this made no difference. I have seen on a number of other forums that people are having this exact problem, so it seems logical that it must be either a simple oversight on our behalfs, or an inherent fault with the machines.

Any updates/findings would be great if you have any. Thanks.

[karthik.mukund]

I have the same problem. Any solutions?

[SpiderBy]

Guys,

I was lucky. My laptop was still under warranty and coincidentally a new problem arose with permanently popping "USB Device Not Recognized" message even if no devices were plugged into USB ports.
After several hours of dealing with Dell support they accepted it is not a software issue and send a technician who replaced the motherboard.
And magically my laptop monitor started to work as well.
So I can confirm in my case it was a problem with the controller on the motherboard.
Though it looks like it was me who damaged it while trying to hook up a new flex cable.
No sure if it is the same problem for you but if you have a new monitor and flex cable then the only remaining culprit is the controller on a mobo...

[Loafmanuk]

Thanks for the reply. I guess there is a very remote possibility that the screen may have damaged the motherboard, as I initially just removed the lcd panel from it without accessing the motherboard at all (no parts or covers removed from the base whatsoever). I only took the keyboard off to gain access to change the cable after it had already failed to light up. Guess Dell will deny any fault even though there are a large number of forum threads all over the world with people having exactly the same issue, which looks to me like an inherent fault. They must have had an enormous number of calls about this issue. I fix laptops for a living, and have never had an issue like this before. By the way, they were quick enough to say it definately had to be the cable and sell me a new one of those! As if they don't know about this issue.... lol!

[dod]

I also have this issue. I am fixing a laptop for someone who cracked her screen. The backlight was working on the damaged screen.

I purchased a new LED HD screen and fitted it but when I turned it on there was no backlight. Only a faint image. I connected back the old screen which had been working except for the crack and no backlight now.

I sent back the screen and the supplier tested it and said it was fine. I am now thinking of replacing the cable but don't think the cable is the issue. I don't know how it could be the motherboard either as I only took the screen apart.
I priced a new motherboard and it's going to be quite expensive to replace. The user contacted DELL already and told them she dropped the screen so I can't get them involved. Does anyone have any ideas????

I also ran a boot diagnostics which gives me "Error Code 2000-0413 LCD Cable not detected"

[ahrp976]

Hi I have the exact same problem with the same laptop.
LED replaced no backlight..diags cable not detected..
would there be a fuse of some kind to protect the screen?

[dod]

Just received new cable and fitted it. No joy!!!!!! Still no backlight. Am going to buy a new mother board and fit it. It's the only thing left I can think off. Dell are useless. This model is only a few months old.