Intermittent Problems; Keyboard, Mouse, Or Pointing Device Problems - Lenovo ThinkCentre Edge 91z Hardware Maintenance Manual

• Ensure that a DVD disc is in the drive with the shiny side of the disc facing down.
• Ensure that video resolution is set to less than 1152 x 864.
• On computers that have a CD-ROM or CD-RW drive in addition to a DVD-ROM drive, make sure that the
DVD disc is in the drive labeled "DVD".
If these actions do not correct the problem, run the diagnostic programs (see "Diagnostics" on page 51 for
instructions). If you need technical assistance, see "Additional information resources" on page 30.

Intermittent problems

Symptom: A problem occurs only occasionally and is difficult to repeat.
Actions:
• Verify that all cables and cords are securely connected to the computer and attached devices.
• Verify that when the computer is on, the fan is not blocked (there is air flow around the fan), and the fan is
working. If airflow is blocked or the fan is not working, the computer might overheat.
• If SCSI devices are installed, verify that the last external device in each SCSI chain is terminated correctly.
(See your SCSI documentation.)
If these actions do not correct the problem, run the diagnostic programs (see "Diagnostics" on page 51 for
instructions). If you need technical assistance, see "Additional information resources" on page 30.

Keyboard, mouse, or pointing device problems

Select your symptom from the following list:
• "All or some keys on the keyboard do not work" on page 41
• "The mouse or pointing device does not work" on page 42
• "The pointer on the screen does not move smoothly with the mouse" on page 42
• "The fingerprint reader does not work" on page 42
• "The wireless keyboard does not work" on page 42
All or some keys on the keyboard do not work
Symptom: All or some keys on the keyboard do not work.
Actions:
• Verify that the keyboard cable is securely connected to the correct connector on the computer.
• If you are using an Enhanced Performance USB keyboard and one or more of the Rapid Access buttons
are the only keys that are not working, these buttons might have been disabled or have not been assigned
to a function. Use the help system in the Enhanced Performance Customization Keyboard program to
help diagnose problems with the Rapid Access buttons.
• On the Windows 7 operating system, do the following:
1. Click Start ➙ Control Panel.
2. Click Hardware and Sound.
3. Click Devices and Printers.
4. Double-click USB Enhanced Performance Keyboard. The USB Enhanced Performance Keyboard
Customization program starts.
.
Chapter 5 Troubleshooting and diagnostics
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