IBM HS20 Hardware Maintenance Manual - Page 34

Small computer system interface messages This information only applies if a storage expansion unit is available. If your receive a SCSI error message when running the SCSI Select Utility program, see "SCSI error codes" on page 87. Note: If the server does not have a hard disk drive, ignore any message that indicates that the BIOS is not installed. Light path diagnostics If the system-error LED on the system LED panel on the front or rear of the BladeCenter unit is lit, one or more error LEDs on the BladeCenter unit components also might be on. These LEDs help identify the cause of the problem. This section provides the information to identify, using the light path diagnostics, problems that might arise. To locate the actual component that caused the error, you must locate the lit error LED on that component. Processor mismatch error LED (CR110) Processor 2 error LED (CR13) NMI error LED (CR17) Temperature error LED (CR31) System board error LED (CR30) Light path diagnostics power present LED (CR111) Reserved (SW3) Light path diagnostics button (SW4) IDE bus 1 error LED (CR14) IDE bus 2 error LED (CR28) DIMM 1 error LED (CR3) Processor 1 error LED (CR12) DIMM 2 error LED (CR5) DIMM 3 error LED (CR4) DIMM 4 error LED (CR6) Figure 5. System board: light path diagnostics For example: A blade server error has occurred and you have noted that the blade server blade-error LED is lit on the blade server control panel. You then: 1. Remove the blade server from the BladeCenter unit. 2. Place the blade server on a flat, static-protective surface. 3. Remove the cover from the blade server. 4. Press and hold the light path diagnostics button to relight the LEDs that were lit before you removed the blade server from the BladeCenter unit. The LEDs will remain lit for as long as you press the button, to a maximum of 25 seconds. 24 BladeCenter HS20 Type 8832: Hardware Maintenance Manual and Troubleshooting Guide