Laptop Backlight not working on Dell XPS L702X

Posted on 2013-12-15
Medium Priority
Last Modified: 2016-11-23
I knocked my laptop on the floor and now the backlight isn't working.
When I shine a torch on the screen I can see Windows, just there is no backlight to illuminate it.
If I look in the back I can only see one cable going into the LCP panel - on other laptops I have seen two - is there another somewhere I'm not seeing that has come loose?

What are the possible reasons for this problem?
What are the options for fixing it? Do I just need a new LCD Panel?
Question by:purplesoup
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 2
  • 2
LVL 88

Assisted Solution

rindi earned 1332 total points
ID: 39719899
The backlight circuit is usually inside the display, and not the PC, so the cable from the PC to the display can be one cable. It probably splits up inside the display, and possibly also the PC part. So open up your case and the display's cover, and check the connections there.

Author Comment

ID: 39720033
Usually I would think the cause is either the inverter, the cable or the screen, but as this is an LCD screen would it not have an inverter, so it would be either the cable or the screen? Is there a way of finding out which it is?
LVL 88

Accepted Solution

rindi earned 1332 total points
ID: 39720061
New laptops don't have an inverter, but they still have some sort of backlight, usually LED backlights. As those don't require high voltage they don't need an inverter. But they still need to be driven. The cable as I mentioned probably splits into at least 2 parts inside the display, one that goes to the panel itself, the other to the backlight part.
LVL 92

Assisted Solution

nobus earned 668 total points
ID: 39720945
here a good site with info on how to test LCD, inverter, and screen :  http://www.lcdparts.net/howto/default.aspx

Author Closing Comment

ID: 39726343
Thanks for all your help

Featured Post

Free learning courses: Active Directory Deep Dive

Get a firm grasp on your IT environment when you learn Active Directory best practices with Veeam! Watch all, or choose any amount, of this three-part webinar series to improve your skills. From the basics to virtualization and backup, we got you covered.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

I originally posted this Article Here (http://www.bestelectronicarticles.com/computers/software-troubleshooting/how-to-find-a-driver-for-you-devices-in-windows.html) and thought I would now share with the Experts Exchange community. Driver Proble…
The Samsung SSD 840 EVO and 840 EVO mSATA have a well-known problem with a drop in read performance. I first learned about this in an interesting thread here at Experts Exchange: http://www.experts-exchange.com/Hardware/Storage/Hard_Drives/Q_2852…
Finding and deleting duplicate (picture) files can be a time consuming task. My wife and I, our three kids and their families all share one dilemma: Managing our pictures. Between desktops, laptops, phones, tablets, and cameras; over the last decade…
Monitoring a network: how to monitor network services and why? Michael Kulchisky, MCSE, MCSA, MCP, VTSP, VSP, CCSP outlines the philosophy behind service monitoring and why a handshake validation is critical in network monitoring. Software utilized …
Suggested Courses
Course of the Month10 days, 18 hours left to enroll

770 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question