IBM 6150 Hardware Maintenance Manual page 122

Step 9
TNL SN20-9850 (05-87) to 75X0152 or 75X0166
Follow the displayed instructions until a service request number or the
ADVANCED DIAGNOSTIC SELECTION menu displays.
DID A SERVICE REQUEST NUMBER DISPLAY?
YES Go to "Step 36" on page 3-0030-36.
NO Continue on the next page.
(5/87) Problem Isolation Charts 3-0030-9