26 Quick Reference GuideDiagnostic LightsCAUTION: Before you begin any of the procedures in this section, follow thesafety instructions in theProduct Information Guide.To help troubleshoot a problem, your computer has four lights labeled 1, 2, 3, and4 on the front panel (see "Front View (Tower Orientation)" on page 18). Whenthe computer starts normally, the lights flash, and then turn off. If the computermalfunctions, use the sequence of the lights to help identify the problem.NOTE: After the computer completes POST, all four lights turn off before booting tothe operating system.Diagnostic Light Codes During POSTLight Pattern Problem Description Suggested ResolutionThe computer is ina normal offcondition ora possible pre-BIOSfailure has occurred.Plug the computer into a working electricaloutlet and press the power button.A possible BIOSfailure has occurred;the computer is in therecovery mode.• Run the BIOS Recovery utility, waitfor recovery completion, and thenrestart the computer.• If the problem persists, contact Dell(see "Contacting Dell" in yourUser’s Guide).A possible processorfailure has occurred.• Reseat the processor (see "Processor"in your User’s Guide).• If the problem persists, contact Dell(see "Contacting Dell" in yourUser’s Guide).
