IBM 6151 Maintenance And Service Manual page 155

Step 23
This step is for flashing numbers only.
Look for the number displayed in the two-digit display in the
following table.
Number Go to Step
02
"Step 24" on page 3-0030-24
30
"Step 24" on page 3-0030-24
99
"Step 25" on page 3-0030-25
DID YOU FIND THE NUMBER IN THE TABLE?
YES Go to the step listed.
NO Go to "Step 25" on page 3-0030-25.
(6/88) Problem Isolation Charts
3-0030-23