106 Troubleshooting ToolsDiagnostic LightsCAUTION: Before you begin any of the procedures in this section, follow thesafety instructions located 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 or back panel. The lights can be off or green.When the computer starts normally, the patterns or codes on the lightschange as the boot process completes. When the computer starts normally,the patterns or codes on the lights change as the boot process completes. Ifthe POST portion of system boot completes successfully, all four lightsdisplay solid green. If the computer malfunctions during the POST process,the pattern displayed on the LEDs may help identify where in the process thecomputer halted.NOTE: The orientation of the diagnostic lights may vary depending on the systemtype. The diagnostic lights can appear either vertical or horizontal.NOTICE - H A R D DR I V E SELF MONITORING SYSTEM H A S R E P O R T E D T H A T AP A R A M E T E R H A S E X C E E D E D I T S N O R M A L O P E R A T I N G R A N G E . DE L LR E C O M M E N D S T H A T Y O U B A C K U P Y O U R D A T A R E G U L A R L Y. A P A R A M E T E R O U TO F R A N G E M A Y O R M A Y N O T I N D I C A T E A P O T E N T I A L H A R D D R I V E P R O B L E M . —S.M.A.R.T error, possible HDD failure. This feature can be enabled or disabled inBIOS setup.Light Pattern Problem Description Suggested ResolutionThe computer is in a normal"off" condition, or a possiblepre-BIOS failure has occurred.The diagnostic lights are not litafter the computer successfullyboots to the operating system.Plug the computer into aworking electrical outlet andpress the power button.A possible BIOS failure hasoccurred; the computer is inthe recovery mode.Run the BIOS Recovery utility,wait for recovery completion,and then restart the computer.A possible processor failure hasoccurred.Reinstall the processor andrestart the computer.
