IBM 6150 Hardware Maintenance Manual page 300

Step 7
If any, exchange the FRUs that are required to run the failing diagnostic
test. Use the removal and replacement procedures in the section for that
FRU.
Try
the failing diagnostic test again.
DID THE SAME PROBLEM OCCUR?
NO Go to "Step 11" on page 3-9860-11.
YES Remove the new FRU and install the old FRU again, then
continue on the next page.
(9/86) Problem Isolation Charts 3-9860-7