IBM System x3650 M3 4255 Service Manual page 74

v Follow the suggested actions in the order in which they are listed in the Action column until the problem
is solved.
v See Chapter 4, "Parts listing, Types 4255, 7945, and 7949 server," on page 157 to determine which
components are customer replaceable units (CRU) and which components are field replaceable units
(FRU).
v If an action step is preceded by "(Trained service technician only)," that step must be performed only by a
trained service technician.
v Go to the IBM support Web site at http://www.ibm.com/systems/support/ to check for technical
information, hints, tips, and new device drivers or to submit a request for information.
Symptom
The OVER SPEC LED on the
light path diagnostics panel is
lit, and the 12v channel A LED
on the system board is lit.
The OVER SPEC LED on the
light path diagnostics panel is
lit, and the 12v channel B LED
on the system board is lit.
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IBM System x3650 M3 Types 4255, 7945, and 7949: Problem Determination and Service Guide
Action
1. Disconnect the server power cords.
2. Remove the following components:
v Optical drive
v Fans
v Hard disk drives
v Hard disk drive backplanes
3. Restart the server. If the OVER SPEC and 12v channel LEDs are still lit,
(trained service technician only) replace the system board.
4. Reinstall the components listed in step 2 one at a time, in the order shown,
restarting the server each time. If the 12v channel A LED is lit, the component
that you just reinstalled is defective. Replace the defective component.
v Fans
v Hard disk drive backplanes
v Hard disk drives
v Optical drive
5. (Trained service technician only) Replace the system board.
1. Disconnect the server power cords.
2. Remove the following components:
v PCI riser-card assembly in PCI connector 1 on the system board
v All DIMMs
v (Trained service technician only) Microprocessor 2
3. Restart the server. If the OVER SPEC and 12v channel LEDs are still lit,
(trained service technician only) replace the system board.
4. Reinstall the components listed in step 2 one at a time, in the order shown,
restarting the server each time. If the 12v channel B LED is lit, the component
that you just reinstalled is defective. Replace the defective component.
v (Trained service technician only) Microprocessor 2
v All DIMMs
v PCI riser-card assembly in PCI connector 1
5. (Trained service technician only) Replace the system board.