IBM PCjr Hardware Maintenance And Service page 142

1. Set the system unit's Power switch to Off.
2. Remove the diskette drive.
3. Turn the diskette drive on its back and check the
diskette-drive drive belt.
IS THE DRIVE BELT INSTALLED ON THE
PULLEYS AND IN GOOD CONDITION?
Replace the diskette-drive drive belt.
Repeat advanced POST and the advanced
tests to ensure that the IBM PCyr is operating
correctly.
3-600-12 Diskette Drive