IBM 7012 300 Series Installation And Service Manual page 54

Step 10
(from Step 9)
1. Set the power switch on the system unit to Off.
2. Connect the serial port extender cable P16 to the system planar.
3. Insert the first diagnostic diskette into the diskette drive.
4. Set the power switch on the system unit to On.
5. Wait for one of the following conditions to occur:
Is c07 or c31 displayed in the three-digit display or is the three-digit display blank?
NO
YES
2-1540-12
Installation and Service Guide
The 3.5-inch diskette drive in-use light is on and c05 or c07 is displayed in the
three-digit display.
The system stops and c31 is displayed in the three-digit display.
The system stops for at least three minutes and a constant number, character, or
symbol other than c31 is displayed in the three-digit display and the power light is on.
The system stops and two or more numbers with values between 221 and 296 are
displayed alternately in the three-digit display.
The system stops and a flashing 888 is displayed in the three-digit display.
The power light does not come on, or the power light comes on but does not stay on.
Exchange the serial port extender cable. Go to "Map 0410: Repair
Checkout" in the POWERstation and POWERserver Common Diagnostics
and Service Guide.
Go to Step 11.