54 Advanced Troubleshootingw w w . d e l l . c o m | s u p p o r t . d e l l . c o mDiagnostic LightsTo help you troubleshoot a problem, your computer is equipped with four lights on theback panel labeled "A," "B," "C," and "D" (see page 72). These lights can be yellow or green.When the computer starts normally, the lights flash. After the computer starts, the lightsremain green. If the computer malfunctions, the color and sequence of the lights identifythe problem.CAUTION: Before you begin any of the procedures in this section, follow thesafety instructions on page 9.Light Pattern Problem Description Suggested ResolutionThe computer is in a normal offcondition or a possible pre-BIOSfailure has occurred.Verify that the computer is pluggedinto a working electrical outlet andthat you have pressed the powerbutton.Memory modules are detected, but amemory failure has occurred.• If you have one memory moduleinstalled, reinstall it (seepage 95) and restart thecomputer.• If you have two or more memorymodules installed, remove themodules, reinstall one modulesee page 95), and then restartthe computer. If the computerstarts normally, reinstall anadditional module. Continueuntil you have identified a faultymodule or reinstalled allmodules without error.• If available, install properlyworking memory of the sametype into your computer (seepage 95).• If the problem persists, contactDell (see page 113).A B C DA B C D= y e l l o w= g r e e n= o f fJ2936bk0.book Page 54 Tuesday, September 2, 2003 3:06 PM
