Apple xserve early 2009 User Manual

Xserve (Early 2009) General Troubleshooting — Block Diagram  21 2010-06-28
Block Diagram   

Xserve (Early 2009) General Troubleshooting — Diagnostic LEDs 22 2010-06-28
Diagnostic LEDs
Logic Board Diagnostic LEDs
The Xserve (Early 2009) logic board includes a set of LEDs to help service providers 
troubleshoot the computer. The LEDs are located on the logic board below the DIMM 
connectors, at the rear of the unit, to the left side of the unit (looking from the back), and on 
the Drive Interconnect Backplane or Xserve RAID Card. 
Some tips:
• You must remove the unit from its rack and place it...

Xserve (Early 2009) General Troubleshooting — Diagnostic LEDs 23 2010-06-28
1. System State LEDs
Use the following table to interpret the LEDs.
LocationNameColorNominalIndicates
S0Power ONGreenOn; off when 
in standby 
mode
System is 
running
S3SleepGreenOff, on when 
Xserve is in 
sleep mode
System is in 
sleep mode
S5StandbyGreenOff; on when 
Xserve is in 
standby
Standby 
mode, 
illuminates 
when AC 
power is 
attached  

Xserve (Early 2009) General Troubleshooting — Diagnostic LEDs 24 2010-06-28
2. CPU Error LEDs
Use the following table to interpret the LEDs.
LocationColorNominalIndicates
CPU_PWRGDGreenOff; on to indicate 
hardware power has 
passed
Power chain in hardware
RSM_RSTYellow, RedOffFault preventing CPU from 
executing instructions
SYS_PWRGDGreenOn at power-on to 
indicate power has 
passed 
Power chain in hardware
PLT_RSTRedOff; on Yellow at 
power on
Platform reset
CPU B OVERTEMPRedOff; on if CPU B core...

Xserve (Early 2009) General Troubleshooting — Diagnostic LEDs 25 2010-06-28
Platform Reset
Normally remains on during standby. This LED flashes on (yellow) briefly at power-on. LED 
should turn off as system powers up and begins to execute instructions. 
Overtemp LEDs
Normally off. These LEDs come on if an error occurs.
If LED is solidly on, it may indicate a processor over-temperature condition. Initial processor 
over-temperature can cause symptoms such as sluggish computer performance. Chronic...

Xserve (Early 2009) General Troubleshooting — Diagnostic LEDs 26 2010-06-28
$Bx = 1 0 1 1 X X X X = All $Bx codes below are memory init codes (x may be any code 0 - F)
$BF = 1 0 0 1 1 1 1 1 = If the unit does not progress past any $Bx memory init codes, this could 
indicate a memory issue regardless of whether DIMM diagnostic error LEDs are ON or not.
$12 = 0 0 0 1 0 0 1 0 = After memory initialization has successfully completed
$51 = 0 1 0 1 0 0 0 1 = Video driver enabled beyond this point. Attached...

Xserve (Early 2009) General Troubleshooting — Diagnostic LEDs 27 2010-06-28
5 & 6. Memory Diagnostic LEDs (A1 - A6 and B1 - B6)
This group of LEDs will normally remain OFF during power-on and throughout normal 
operation. If any of these LEDs come ON RED, this indicates that the corresponding DIMM (or 
its slot) may be faulty. To verify whether the fault lies with the DIMM or the slot, power down 
the unit and move the DIMM to another slot. If the DIMM is faulty, the LED adjacent to its new 
slot should...

Xserve (Early 2009) General Troubleshooting — Diagnostic LEDs 28 2010-06-28
7. Reset Buttons
System Management Controller (SMC) Reset
The System Management Controller (SMC) is a chip on the logic board that controls all power 
functions for the Xserve. If the Xserve is experiencing any power issue, resetting the SMC may 
resolve it. The SMC controls several functions, including:
• Telling the Xserve when to turn on, turn off, sleep, wake, idle, and so forth
• Handling system resets from various commands...

Xserve (Early 2009) General Troubleshooting — Diagnostic LEDs 29 2010-06-28
5. Press the power button to start up the Xserve.
Power ON / OFF Button
Behaves exactly like the front panel power button, and can be used as an alternate way to turn 
the unit on and off if needed.
Reset Buttons
When pressed, resets CPUs regardless of what is currently running. This reset overrides all 
software processes and restarts the system. Use with caution as this form of reset may corrupt 
software or files on a drive....

Xserve (Early 2009) General Troubleshooting — Diagnostic LEDs 30 2010-06-28
bay and the controller has recognized this event. The LED will turn ON GREEN again when the 
corresponding drive module has been removed from its bay. 
Since there are only three drive bays, the fourth I/O channel and LED are not used and should 
remain ON GREEN during normal operation.
When you power-on the system, you should see the following activity sequence on these LEDs:
1. The entire group of eight LEDs should come ON...