During normal operation, the keyboard status lights display the current status (on or off) of the Num Lock, Caps Lock, and Scroll Lock features. If the computer starts without error, the lights flash, and then turn off. If the computer malfunctions, however, you can use the status of the lights to help identify the problem. Diagnostic Light Codes During POST To troubleshoot a problem with your computer, read the sequence of the keyboard status lights in order from left to right (Num Lock, Caps Lock, and then Scroll Lock). If the computer malfunctions the individual lights display a status of either On , Off , or Flashing . Hardware Troubleshooter If a device is either not detected during the operating system setup or is detected, but incorrectly configured, you can use the Hardware Troubleshooter to resolve the incompatibility. Microsoft® Windows® XP: 1. Click Start® Help and Support. 2. Type hardware troubleshooter in the search field and press to start the search. 3. In the Fix a Problem section, click Hardware Troubleshooter. 4. In the Hardware Troubleshooter list, select the option that best describes the problem and click Next to follow the remaining troubleshooting steps. Microsoft Windows Vista®: CAUTION: Before working inside your computer, read the safety information that shipped with your computer. For additional safety best practices information, see the Regulatory Compliance Homepage on at: NOTE: After the computer completes POST, the Num Lock light may remain on, depending on your BIOS settings. For more information on using the system setup program, see the Dell™ Technology Guide on your computer or at support.dell.com. NOTE: If your computer displays any of the diagnostic light codes below, try shutting down your computer, removing all external devices or the media base, and starting your computer. If the diagnostic light code is still indicating a problem, continue troubleshooting below. Light Pattern Problem Description Suggested Resolution Memory modules are detected, but a memory failure has occurred. l If available, install working memory of the same type into your computer (see Memory). l If the problem persists, contact Dell Support. System board failure has occurred. l Contact Dell Support. A possible processor failure has occurred. l Contact Dell Support. A possible LCD failure has occurred. l Reseat the display cable (see Removing the Display Assembly). l If the problem persists, contact Dell Support. A possible keyboard failure has occurred. l Reseat the keyboard (see Removing the Keyboard). l If available, connect an external keyboard. l If the problem persists, contact Dell Support. 1. Click the Windows Vista start button , and click Help and Support. 2. Type hardware troubleshooter in the search field and press to start the search. 3. In the search results, select the option that best describes the problem and follow the remaining troubleshooting steps. Dell Diagnostics When to Use the Dell Diagnostics If you experience a problem with your computer, perform the checks in Solving Problems, and then run the Dell Diagnostics before contacting Dell for assistance. Start the Dell Diagnostics from your hard drive or from the Drivers and Utilities media provided with your computer. Starting the Dell Diagnostics From Your Hard Drive Before running the Dell Diagnostics, enter system setup to review your computer's configuration information, and ensure that the device you want to test is displayed in system setup and is active. For more information on using the system setup program, see the Dell™ Technology Guide on your computer or at support.dell.com. The Dell Diagnostics is located on a separate diagnostic utility partition on your hard drive. 1. Ensure that the computer is connected to an electrical outlet that is known to be working properly. 2. Press and hold the key and then turn on your computer. The computer runs the Pre-boot System Assessment (PSA), a series of initial tests of your system board, keyboard, display, memory, hard drive, etc. . During the assessment, answer any questions that appear. . If failures are detected during the Pre-boot System Assessment, write down the error code(s) and contact Dell Support. . If the Pre-boot System Assessment completes successfully, the following message appears: "Booting Dell Diagnostic Utility Partition. Press any key to continue." 3. Press any key to start the Dell Diagnostics from the diagnostics utility partition on your hard drive. 4. Press to select Test System and then press . 5. At the Dell Diagnostics Main Menu, left-click with the touch pad/mouse, or press and then , to select the test you want to run (see Dell Diagnostics Main Menu). 6. After all tests have completed, close the test window to return to the Dell Diagnostics Main Menu. 7. Close the Main Menu window to exit the Dell Diagnostics and restart the computer. CAUTION: Befo...
