2 Hardware Maintenance Manual: IBM PC Server/Enterprise Racks

b. Server selector cable (connects between the server selector keypad and
the server selector unit).
c. Server selector keypad.
d. Server selector unit.
•YES: Power-off the server rack and replace the server rack components in the
following order until the problem goes away. See “Powering off the rack” on
page 3.
a. Device extender cable (connects between the device and the server
selector unit)
b. Failing device
c. Server selector cable (connects between the server selector keypad and
the server selector unit)
d. Server selector keypad
e. Server selector unit
Power checkout
Use the following procedure for diagnosing power problems for the IBM PC Server
Rack Enclosure and IBM Rack enclosure (Type 9306).
Attention:
•For Models 4QS, 4QX, 9QS, 9QX, 9TS, 9TX only:
Ensure that the voltage selector switch on e ach server installed in the server rack
is set to 230 V ac.
•For Models 200, 900 only:
Ensure that the voltage selector switch on e ach server installed in the server rack
is set to the proper voltage as supplied by the Power Distribution Unit, PDU.
1. Check the following:
•Ensure the external power cord is in good condition and properly connected
to a known-good power source.
•Ensure the internal power cables are in good condition and properly
connected. (The internal power cables connect between the power
distribution unit and the servers installe d in the server rack.)
•Ensure the following devices are powered on.
a. Power distribution unit
b. Server selector unit
c. All system units
d. Display
2. If the items/conditions in step 1. are not okay, correct the problem and verify
correct operation of the server rack.
3. If the items/conditions specified in step 1. are okay, then, using the server selector
keypad buttons, check for correct operation of all the servers installed in the rack.
4. Did the failure occur on more than one serve r?
•No: Go to the Hardware Maintenance manual for the server that was selected
when the failure occurred and run the server diagnostic programs. If the
problem still remains, replace the power distribution unit.