[SOLVED] Dark LED display on Dell Inspiron 1545

[SilverLeaf]

When this laptop came in it had an image on the screen, but no backlight. My initial reaction was that is was probably a bad inverter or backlight. After checking the specs, however, this model has an LED panel, hence no inverter. It powers an external monitor just fine.

Next, I found this article relating to a possible issue with a blown fuse (tiny SMD). Fuse checked out fine with a meter (low resistance across fuse), so I ruled that out.

I replaced the LCD cable, as well as the sensor for the magnet in the lid, and still no luck. I guess the next step is to replace the panel itself (not outrageous, but not cheap either). But, I wonder how common it is that an LED backlight would actually fail? I mean, LED's are generally pretty durable and don't usually go bad on their own.

Any thoughts or experiences with similar issues?

 

[732914TECH]

Ive had the dark screen problem with an LED screen as well and I was able to replace the lcd screen itself and it was fine, I guess if you have no way of hooking up a test screen youll just have to hope thats the case.

 

[javjim]

you can change the leds but its hard to find the leds

usually its like changing a backlight on a lcd

 

[NYJimbo]

you can change the leds but its hard to find the leds

usually its like changing a backlight on a lcd

Its not likely the LEDs themselves.

 

[Jobrien]

I had the same thing with a macbook.. turned out to be the board..

 

[seedubya]

We've had this issue 4 times now - it seems to be whatever is providing power to the led's
No joy in repairing in any case. I mean new screens and new cables but no result in any case.

 

[14049752]

I've dealt with several of these. The fuse has always been the problem each and every time. It's not always labeled the way they say in the article, though...Sometimes (if you're lucky) you can see the damaged fuse...bust most times you just have to carefully check it over.

I'd double check all of the fuses around the video connector again, just to be sure.

 

[ectta]

When this laptop came in it had an image on the screen, but no backlight. My initial reaction was that is was probably a bad inverter or backlight. After checking the specs, however, this model has an LED panel, hence no inverter. It powers an external monitor just fine.

Next, I found this article relating to a possible issue with a blown fuse (tiny SMD). Fuse checked out fine with a meter (low resistance across fuse), so I ruled that out.

I replaced the LCD cable, as well as the sensor for the magnet in the lid, and still no luck. I guess the next step is to replace the panel itself (not outrageous, but not cheap either). But, I wonder how common it is that an LED backlight would actually fail? I mean, LED's are generally pretty durable and don't usually go bad on their own.

Any thoughts or experiences with similar issues?

agree, but no one can know how long it can use? also no one know exactly how the user uses it to cause the problem.

perhaps borrow a similar LED panel to test any problem with the cable first, isolate the problem from cable and mobo, then u can choose to get another LED to replace if you can't repair it.
refresh LED firmware, we don't have it, but refresh LCD firmware, we tried many times.

 

[SilverLeaf]

Thanks for all the input. Turns out it was indeed the LCD panel. Fitted the new one, and all is fine.

I'm glad it didn't turn out to be a fuse. Those things are TINY! I've done a little SMD soldering before, but nothing near that pitch.

 

[NYJimbo]

Thanks for all the input. Turns out it was indeed the LCD panel. Fitted the new one, and all is fine.

It's kind of sickening to think that the purpose of going to LED based LCD's was to eliminate the problems of CCFL/inverters but here we are replacing LCD units today because it's the stupid circuit boards firing the LED's and not the lighting mechanism (LED) itself.

I am sure the problem was the logic board on the panel, not the actual LED's but you can't replace those so its a total rip and replace.

The one upside to all this is that LED based LCD's seem to really be dropping in price. I just ordered one for a toshiba satellite p755 and it was $59, that's incredible compared to what I used to pay a few years ago. So even if they still fail at least we replace LCD, "ccfl" and "inverter" at the same time for less than we used to pay.