28 Apr, 2009
Laptop LCD Troubleshooting Tips
Posted by: Ecomer In: LCD Screen Repair ()
“I replaced the laptop screen today and I have no picture at all. I can see the backlight come on and an external monitor works fine… a friend said maybe a driver but I am lost at this point.. this computer has been hooked to an external monitor for about 3 years if that matters at all.
I have a Dell Inspiron 6000.”
It’s not a driver related issue. If you can see video on the external monitor, most likely the driver works properly.
Have you tried reconnecting the video cable to the motherboard?
It’s possible the cable is not making good connection with the motherboard or the cable is bad and has to be replaced. Also, there could be a problem with the motherboard but I would try replacing the video cable first.
By the way, I assume that you purchased the LCD screen from a reliable source and it’s good.
2.Laptop LCD lights up but there is no image.
“The backlight on my laptop LCD lights up..but there is no image. Even when its Posting (before booting in the OS) there is no image. HOWEVER if i put pressure on a corner of the LCD, the image shows up. Is it a bad inverter or video cable or other?”
This problem is not related to the inverter. Your LCD screen lights up (even without image) so the inverter board and the backlight lamp work fine.
Most likely you have a problem with the LCD screen and it has to be replaced. Apparently, the LCD controller board has a bad solder joint and it makes contact only when you press on the screen.
Could it be a bad video cable or loose connection? Yes, but not likely. Just in case, you can try reseating the video cable connection on the back of the LCD screen and even replacing the cable. If you still have the same problem, you’ll have to replace the LCD screen.
3.A vertical row of pixels appeared on the LCD screen. Cable, inverter or LCD?
“Couple of months ago, a vertical row of pixels was shown in yellow, and 2 weeks ago, a 4cm row of pixels on the right side of the LCD was blurred and after couple of days, it went completely white. Same this is now happening in the left side, and i’m afraid it will shortly turn into white as well. Can this be caused by the graphic cable or by the inverter, or is this the LCD dying on me…?
By the way, it’s a Toshiba Satellite P105-S6084.”
This problem is not caused by the inverter board because you still can see the image on the screen. The backlight still works, so it’s not the inverter.
Also, it’s not related to the LCD cable. A bad faulty LCD cable affects image on the whole LCD screen, not just on a part of the LCD. I don’t think that your problem is related to the cable.
Apparently your LCD screen is dying and you’ll have to replace it soon.
Just in case, test the laptop with an external monitor attached to the VGA port on the side of the laptop. Most likely the external video will be fine. Let me know if the external video output also has vertical rows of pixels. Because if it does (I really doubt it), there could be a problem with the video card.
4.Notebook turns on but monitor would not show any image
“I have a Toshiba Satellite notebook. Recently, and for no apparent reason, when I pushed the power button to turn on my notebook, the computer would turn on, but the monitor would not show any image or even any sign of light (doesn’t even light up). Is this possibly a driver issue, or will I have to get a new monitor.”
No, it’s not a driver issue because this problem occurs as soon as you start the notebook, even before Windows (and drivers) start loading.
First, you’ll have to test your notebook with an external monitor attached to the VGA port on the side of your notebook. If both internal and external monitors have no image, this problem is not related to the notebook screen.
That could be memory related problem. Try reconnecting the memory module. If you have two modules installed, remove them one by one and test the laptop with each module separately. It’s possible that one of the memory modules is bad and your notebook will start as soon as you remove bad RAM.
5.Laptop shows a blank white screen even with a new LCD
“I bought an old Toshiba Satelite which arrived with a smashed screen, when switched on showed a blank white screen, changed screen, still lights up white. Changed the screen lead, still lights to a blank white screen. External VGA works fine. Whats left motherboard perhaps?. Am I right in thinking that it cannot be the inverter as the screen lights up.”
You are correct. If the screen lights up (even without any image), the inverter board works properly.
You’ve replaced the LCD screen with video cable but still experience the same problem, so it must be related to the video card. Most likely the video card is integrated into the motherboard, so it’s the motherboard problem.
6.Notebook screen flickering a rainbow of colors
“I have problem with my screen flickering a rainbow of colors even when I was at the Windows bootup logo. But when i using a video output everything is fine. Any Idea?
I have a Compaq Presario V3000 Series Notebook PC.”
The external video works fine, so your problem is not software related. I don’t think it’s motherboard or video card related problem either, otherwise you would get garbled video on the external monitor.
You can have this problem because of:
1. Loose connection between the video cable and the LCD screen. Try reseating connection on the back of the LCD screen.
2. Loose connection between the video cable and the motherboard. Try reseating connection on the motherboard.
2. Bad video cable. Try replacing the cable.
3. Defective LCD screen. Replace the screen.
4. Problem with the motherboard but it’s not very likely.
7.Random black screen from time to time
“My problem is that i am getting a random black screen from time to time, this happens while using various apps from internet explorer to my dj software. When this happens the backlight is still on (clearly visible in a dark room. I thought i would try hooking it up to my desktop monitor when this happened the last time, to my surprise it worked fine, it had not crashed, clear image on the external monitor, black screen on the laptop display (but the back light was on). Any ideas as to what could be causing this?”
1. Make sure you are running the latest version of BIOS. Download and upgrade the BIOS if needed, it might have a fix for your intermittent video problem.
2. It’s possible that the video cable is not making good connection with the LCD screen or motherboard. Reconnecting/reseating the cable might help.
3. Could be bad video cable or LCD screen.