Lenovo 7390 User Manual page 71

7. Look for a build up of dirt on the plastic rollers 3 inside the ball cage. This
build up usually appears as a stripe running across the middle of the rollers.
8. If the rollers are dirty, clean them by using a cotton swab soaked in isopropyl
(rubbing) alcohol. Turn the rollers with your finger and continue swabbing
them until all the dirt is removed. Be sure the rollers are still centered in their
channels after you clean them.
9. Remove any fibers from the swab that might be remaining on the rollers.
10. Replace the ball and the retainer ring. Twist the retainer ring to the locked
position.
11. Reconnect the mouse cable to the computer.
12. Turn your computer back on.
Chapter 7. Troubleshooting and diagnostics
53