98 IBM System x3850 X6 and x3950 X6 Planning and Implementation GuideFor details about this technology, see the Trusted Computing Group (TCG) TPM MainSpecification at the following website:http://www.trustedcomputinggroup.org/resources/tpm_main_specification3.19.4 Light path diagnosticsLight path diagnostics is a set of LEDs located on server’s components that help to determinefailed component. If server’s component failed or has error, then appropriate LEDs light up onthe front operator panel, the light path diagnostics panel and on the failed component. Bychecking the LEDs, you can locate the failed component.If an error occurs, check the LEDs on the front operator panel first. If the check log LED is lit,check IMM event log or system-event log. If the system-error LED is lit, find the appropriatecomponent with lit LED. Figure 3-33 shows the location of LEDs on the front operator panel.Figure 3-33 Front operator panel LEDs locationFor example, if a Compute Book error occurs, the Error LED located on the appropriateCompute Book should light up. Figure 3-34 shows the LED locations on the Compute Book.Figure 3-34 Compute Book’s LEDs locationIf the Compute Book has a memory error, appropriate LEDs located on the Compute Book’ssystem board can help to determine the failed DIMM. To use this feature, you have todisconnect the server from power, remove the Compute Book from the server, press the Lightpath button located on the front panel of the Compute Book, and find the lit LED on thesystem board. The DIMM LED that is lighted up points to the failed memory module.Power button LED Locate button LED Check log LEDSystem error LEDPCIe slot 11 error LEDPCIe slot 12 error LEDBoard error LEDDDR3compute bookPowerLEDErrorLEDLight pathbuttonFanLEDFanLED
