IBM H Series Installation And Service Manual page 279

to the new unit per step 7 in "Power Supplies and Power Supply Fan
Assemblies" on page 7-21.
If the INTERNAL fans spin and the green LED is on solid, then hold the test
switch for at least 30 seconds.
If the INTERNAL fans stop or the green LED goes off before 30 seconds
then replace the power supply and move the external fans from the defective
unit to the new unit per step 7 in "Power Supplies and Power Supply Fan
Assemblies" on page 7-21.
If the INTERNAL fans and the green LED stay on for 30 seconds, then the
power supply has passed its internal self-test. All output voltages are
working within specifications. Look for other possible causes before
replacing the power supply.
7-25
Chapter 7. Removal and Replacement Procedures