IBM 6151 Maintenance And Service Manual page 387

Step 3
Look at the slot position you recorded for the boards removed from
slots Band D.
Ii
.-
AJZB085
DID YOU REMOVE A BOARD FROM SLOT D?
NO
Set the power switch on the system unit to Off; then go to
"Step 5" on page 3-9810-5.
YES Continue on the next page.
(6/88) Problem Isolation Charts 3-9810-3