LCD Lines: Common Causes

Back in April last year, Lionel blogged about a vertical line issue that could potentially affect customers who own 17" Inspiron 9200, 9300, and XPS Gen 2 notebook LCDs.

After engaging our engineering and product group teams, as well as the LCD manufacturer, to investigate and isolate the cause of this issue, we narrowed the problem down to a specific part within a certain date range. During that research, we found that the part may also affect the Inspiron 6000, 8600, Latitude D800, D810, and Precision Mobile Workstation M60 and M70 LCDs. That led to Lionel's second blog post on the topic.

We've taken steps to contact those who may be affected to offer a warranty replacement and also put in place measures to rectify any out of pocket expense incurred by out of warranty customers who replaced the affected screens in the past.

Since then, comments have hit our forums and blog site about other potentially affected systems and possible causes and fixes for them. We've gone back to our engineering and product group teams and verified that the part causing this issue:

  • has been purged from our production line, and
  • has not been used in any other system type

Both of these questions have been confirmed and no other system outside of the date range or listed system types are affected by this part.

That said, there are other variables that can lead to vertical and horizontal lines on other system types regardless of size or model. Lines on an LCD can appear sporadically, at random places on the screen, and for what appears to be for no reason at all. These lines can be caused by normal LCD failures brought on by a multitude of variables, which I'll try to cover here. Vertical lines tend to be a more common issue in notebooks, primarily because they are subjected to more wear and tear on a daily basis than a desktop LCD.

The most common cause of these lines is simply a loose connection. As notebook systems are carried around, no matter how careful we try to be, they have a tendency to be bumped, jarred, and even sometimes the heart stopping drop. Though  today's notebooks are designed to better absorb and dissipate small shocks, it can still have adverse affects on the notebook's internal components. A good bump or series of bumps and random movements can cause the LCD cable to become loose. The connection remains intact, but some breaks in the signal can lead to impurities in the reproduction of the image on the screen. Think of a loosely-fastened garden hose… water will still be directed and outputted through the end of the hose, but some water is lost at the connection. This is easily fixed by tightening the hose. Similarly, the LCD can usually be fixed by simply making sure the connection is secure. (Service manuals for Dell systems can be found here on support.dell.com.)

A golden rule of any seasoned technician when it comes to cable connections: don't just check the connection, reseat it. This applies to more then just cable connections (memory, wireless cards, hard drives, optical drives, etc…) There are a few reasons for this, the first being temperature. With so many components designed into such a small case, heat is inevitable. These temperature variations can lead to things like "chip creep" and oxidation. Removing the cable and firmly, but carefully reseating it should solve this problem by not only making sure that the connection is properly seated, but also that the pins are free from oxidation.

The second reason is debris. If you've ever opened up your notebook to clean the keyboard or for maintenance, you might see any number of things such as food particles, hair, paper, dirt and dust. Some of these objects are small enough to get into the connections and cause problems. This is one of the reasons that regular cleaning of your notebook and desktop PCs should be done. The problems caused by debris can usually be quickly cleared up by a can of compressed air and a little time and effort.

If these simple fixes don't seem to work, then we need to look at the actual failure possibilities. Vertical or horizontal lines that don't disappear after the basic troubleshooting are usually caused by circumstantial failures. The most common type of failure that leads to lines on the display is an open circuit connection between the driver IC (flexible circuit board) and LCD glass. This is usually caused by external stresses (mechanical, thermal, etc…), which causes the flex circuit to detach from the glass. The variables leading to the detachment are wide and are dependant on individual cases. With the amount of travel and various operating environments of a notebook, pinpointing the exact cause can be near impossible, unless of course the problem immediately follows a catastrophic event such as dropping the notebook or prolonged exposure to heat or cold, such as leaving the system in a car.

Investigations into technical problems, including which systems, batches, and date ranges are affected, are rigorous, and we strive for accuracy. Unfortunately, not every technical problem can be traced down to the root cause. But in every case, we try to proceed appropriately and in all fairness to affected customers.

If you are experiencing any problem with lines on your LCD and your system is not one of the potentially affected units, or in the date range outlined in Lionel's earlier posts, please contact technical support to troubleshoot and identify possible fixes. See below for details on how to do that.

For customers in the United States:

  • U.S. Inspiron Technical Support: 1-800-624-9896
  • Say "Technical Support"
  • Enter your Express Service Code or say, "I don't have it"
  • Is your system for Personal or Business use?
  • Say "Notebook"
  • Is your system an Inspiron, XPS, Latitude or Precision

For customers outside the United States:

Go to support.dell.com

  • Choose your country or region from the drop-down list
  • Choose Contact Us
  • Choose Technical Support
  • Choose Call Technical Support

About the Author: Mike Basore