IBM iSeries Series Hardware Problem Analysis And Isolation page 185

3. Perform the following:
a. Power off the system.
b. Disconnect all the I/O devices (tape, diskette, optical, and disk units) from the expansion unit or
I/O tower you are working on by sliding them partially out of the unit (see Remove and replace
procedures).
c. Remove and label all cards installed in the PCI card area.
d. Power on the system.
Does a power reference code occur?
v Yes: Continue with the next step.
v No: Go to step 10 (See page 174).
4. Perform the following:
a. Power off the system.
b. Remove one of the air moving devices (AMDs) from the expansion unit or I/O tower that was not
previously removed during this procedure. (Disregard an AMD SRC if it occurs during this step.)
c. Power on the system.
Does a power reference code occur?
v Yes: Continue with the next step.
v No: The AMD you removed in this step is the failing item.
This ends the procedure.
5. Have you removed all of the AMDs one at a time?
v No: Perform the following:
a. Power off the system.
b. Install the AMD that was removed in step 4 (See page 173) in the original location.
c. Repeat step 4 (See page 173).
v Yes: Install all the AMDs and continue with the next step.
6. Perform the following:
a. Power off the system.
b. Remove the expansion unit or I/O tower power supply cables, that was not previously removed
from one of the DASD backplanes.
c. Power on the system.
Does a power reference code occur?
v No: The DASD backplane that was disconnected in this step is the failing item.
This ends the procedure.
v Yes: Continue with the next step.
7. Have you disconnected the power cables from each of the DASD backplanes one at a time?
v Yes: Continue with the next step.
v No: Repeat step 6 (See page 173).
8. Perform the following:
a. Power off the system.
b. Remove a power supply that was not previously removed and replace it with the new one.
c. Power on the system.
Does a power reference code occur?
v Yes: Continue with the next step.
v No: The power supply that was removed in this step was the failing item.
This ends the procedure.
Analyze hardware problems
173