Dell Inspiron 1545 Dim LED

[incradibles]

Hi
I have a problem with dell inspiron 1545 when i turn it on a dim display comes on the led screen while a normal on external display i have changed the led's but no backlight comes on always dim so may be its gpu issue or cable.

[tschanuka]

Re: Dell Inspiron 1545 Dim LED

Hi.

Yes defective GPU and cable can cause such problems, but also other parts of the motherboard for power and backlight controls the display.

I uploaded LVDS part of the schematic for you to check:
http://ultrashare.net/hosting/fl/a9bbf0ba2a/lvds

[momaka]

Re: Dell Inspiron 1545 Dim LED

If an external monitor looks normal, then it's unlikely that the GPU is defective.
Have a look at the backlight controller instead or the circuit that controls the backlight brightness.

[jsog]

Re: Dell Inspiron 1545 Dim LED

Blown fuse? http://forum.notebookreview.com/dell...cklight-5.html

Post #48 shows a picture, don't know if it's the Inspiron 1545 but should at least be similar.

Don't do what they do there! Bridging a fuse is asking for trouble. But it might help you locate and test the fuse, then people here can help locate a replacement.

[tschanuka]

Re: Dell Inspiron 1545 Dim LED

@momaka:
Hi, I agree with you.
But display backlight is controlled/enabled by the North/GPU in this model.
That part or connection of the chip can also fail as the other functions like graphic processing.
Yes, it is not much likely if there are no other signs of GPU or Northbridge failures. It could just not be excluded, that´s why I mentioned it.

I think the hint from jsog is a good point to start.
LED Backlight issues seem to be a common problem with the 1545.

[Linkk]

Re: Dell Inspiron 1545 Dim LED

Hi,

Does anyone know what the capacitor next to the fuse is (C69) ?, as i've managed to knock it off and damage it whilst taking off the fuse, I've taken a picture of mine, its the same board.

[marcellodj]

Re: Dell Inspiron 1545 Dim LED

I had same problem with a packard bell: video ok on svga out, no blue screen or other problems, but no video on panel with ccfl on, tried to change panel, same result.

Reflowed gpu and now is perfectly working.
Best regards

[momaka]

Re: Dell Inspiron 1545 Dim LED

Does anyone know what the capacitor next to the fuse is (C69) ?, as i've managed to knock it off and damage it whilst taking off the fuse, I've taken a picture of mine, its the same board.

If the capacitor doesn't appear to be physically broken, check it for short circuit with a multimeter. If it doesn't appear short-circuited, just solder it back into place again. Otherwise if it is broken or shorted, just find a cap of the same size from other scrap motherboards.
It looks like C69 is a decoupling cap, along with C68, so the board will probably work without it fine. It's still a good idea to place a cap of some sort in that spot, though.

[tschanuka]

Re: Dell Inspiron 1545 Dim LED

C69 is 1uf 50v.

[incradibles]

Re: Dell Inspiron 1545 Dim LED

Thanks guys i got fuse defaulter, i changed with new one i giot back my screen back light. you guys are rocking thanks again

[spidey]

Re: Dell Inspiron 1545 Dim LED

i need the schematic of this board!!! searching but havent found yet. if someone shares, would be great.

[spidey]

Re: Dell Inspiron 1545 Dim LED

i'm changing lcd screen with led one, i'm using the 3m converter cable lcd to led display. I want to find the vin, brightness, gnd and on/off control. it was easy to find vin and gnd. But now i have 6 more cables to connect but only 2 of them. i have one +3v(i guess on/off this one) and the rest are no voltage. does anyone know the brightness signal, so i can measure it with the scope. Fuse was blown, i bridged it. 10.8 vin i have.