Advanced Troubleshooting 55Advanced TroubleshootingDiagnostic LightsCAUTION: Before you begin any of the procedures in this section, follow the safety instructionslocated in the Product Information Guide.To help you troubleshoot a problem, your computer has four lights labeled "1," "2," "3," and "4"on the front panel (see page 72). When the computer starts normally, the lights flash. After thecomputer starts, all four lights display solid green. If the computer malfunctions, the color andsequence of the lights identify the problem.Light Pattern Problem Description Suggested ResolutionThe computer is in a normal "off" condition ora possible pre-BIOS failure has occurred.The diagnostic lights are not lit after thesystem successfully boots to the operatingsystem.Plug the computer into a working electricaloutlet. Also see "Power Problems" on page 48.A possible processor failure has occurred. Reinstall the processor (see page 110) andrestart the computer.Memory modules are detected, but a memoryfailure has occurred.• If you have two or more memory modulesinstalled, remove the modules, reinstall onemodule (see page 79), and then restart thecomputer. If the computer starts normally,reinstall an additional module. Continueuntil you have identified a faulty module orreinstalled all modules without error.• If available, install properly working memoryof the same type into your computer (seepage 79).• If the problem persists, contact Dell (seepage 139).D8659bk0.book Page 55 Thursday, March 10, 2005 10:18 AM
