IBM 6151 Maintenance And Service Manual page 175

Step 5
Listen to the tape drive.
A,JZR227
IS THE NOISE COMING FROM THE TAPE DRIVE?
YES The tape drive is causing the noise.
1. Exchange the tape drive.
2. Run the System Checkout.
3. This completes the repair.
NO
Follow the procedures for servicing the device that has the
noise problem.
(6/88) Problem Isolation Charts
3-0050-5