4-14 Troubleshooting and RepairTable Section 4-3 Problems and SolutionsProblem Symptom SolutionKeyboard or mousemalfunctionMonitor has prompt, but cannotinput data.1. Check that keyboard/mouse isplugged in.2. Check password utility (seeSection 2).3. Disable password utility (seeSection 2).4. Replace keyboard (or mouse).5. Replace system board.CommunicationerrorNo or bad data whencommunicating.1. Check cable connections betweensystem board and device.2. Check that the interface port isselected.3. Test or replace device and interfacecable.4. Replace system board.Diagnostic Output and Beep CodesOne beep indicates that the computer has completed its power-on self-test. If intermittentbeeping occurs, power off the computer and try again. If the beeping persists, see TableSection 4-5 for diagnostic outputs and beep codes.The diagnostic port output codes are placed at the diagnostic status port (port 80) to indi-cate tests in progress and failed tests to someone with hardware that can detect the output.If the FAILBEEP option is selected, the Beep codes are announced on the speaker only if afatal failure is detected. For instance, “2-2-3” (a burst of two beeps, a burst of two beeps, aburst of three beeps) indicates a failure of the BIOS ROM checksum. Both sets of codes areonly used prior to screen initialization and screen retrace verification. Once the screen isbelieved operable, diagnostic reporting is via screen messages.Table Section 4-5 Diagnostic Output and Beep CodesCode Beeps Description of Test or Failure at POST02 verify real mode04 get CPU type06 initialize system hardware
