# laptop monitor not detected, only external works.



## Netcat2010 (Oct 8, 2010)

This morning I woke up and my Acer Aspire 5100 laptop monitor was blank. I have an external monitor and that works fine. I could see my mouse arrow on the external monitor but not the taskbar/start menu since that's on the main monitor. I could tell the laptop monitor was being detected because my mouse arrow would slide over into it if I tried. But without being able to see the taskbar/start menu, I couldn't get to any of my applications. I found that if I press FN+F5 over and over, I can get the main screen to come on but only for a few seconds. Sometimes it's dim and always it goes blank again in 3 or 4 seconds. But by repeatedly doing this, I was able to move the taskbar to the secondary monitor and thus make the computer semi-functional. 

I disconnected the external monitor and re-booted and saw that the screen was very dim and then went dark during the boot-up process. No usual DOS-style lettering scrolling across the screen. But the computer does boot up and again if I press FN+F5 over and over, I can see the screen long enough to log in and move some windows to the secondary monitor.

Right now I'm at work and the laptop is unplugged with the battery out. I'll try it again tonight and hope for the best. I'm not sure what else to try.


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## dai (Jul 2, 2004)

sounds like the backlight/inverter


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## leo_kendall (May 11, 2010)

there isn't no display on the screen at all. the lcd display is turned off no life untill windows turns it on.


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## stylishjm (Sep 29, 2010)

Plug the external monitor in, then go to display properties, and set the laptop display as active / primary


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## GZ (Jan 31, 2010)

As dai stated, your issue seems to be a backlight issue. Take a flashlight (turned on) and shine the beam directly into the screen, you should be able to see the images on the screen. 

Unfortunately, trying to figure out which is the problem (the backlight or inverter) is a bit of a pain, because both have extremely similar symptoms. My experience leads me to believe your issue lies with the inverter, and since the inverter is the cheapest part (and easiest to replace) I will suggest you replace that first.

Used from eBay.com

New from Buy.com

Keep in mind that you are gambling with used parts, although the part may be perfectly fine and last you for the life of the computer, it may also prematurely fail. A new unit usually has a warranty/return period in case of defect.

Be sure to remove the inverter and cross-reference the part number before making a purchase.

Here is a guide for disassembly of your laptop.


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## leo_kendall (May 11, 2010)

ok first of let me say that it'snot the back light. There is no life to the monitor at all. Even if i shine a light the brightness of the sun at it there is no image. 
i'm my spare time i repairs laptops desktops etc for sun, so i'm pretty familiar with pc's.

now this leads me to the inverter. If the inverter was the problem why would i only get the display right after windows loads it's display drivers? After everything is loaded everything works perfect.

I think the problem may lie in the bios or something is crossed or grounded on the laptop in which the bios thinks there is an external monitor hooked up at all time. there is no options in the bios for anything besides boot up sequence. and date and time. 

Like i said i have a work around to get to the bios by hooking up an eternal monitor or use my vga to rca/s-video box to hook up to a normal tv.

thanks for the suggestions, would love to here new ones.


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