100 Troubleshooting and problem solvingPSU LEDsSee Figure 28 (page 34) for a visual description of the Power Supply Unit (PSU) module faceplate.Fan cooling module LEDsSee Figure 29 (page 35) for a visual description of the Fan Cooling Module (FCM) faceplate.Ops panel LEDsThe Ops panel displays the aggregated status of all the modules. See also Figure 32 (page 38).Table 17 PSU LED statesCRU Fail(Amber)AC Missing(Amber)Power(Green) StatusOn Off Off No AC power to either PSU.On On Off PSU present, but not supplying power or PSU alert state.(usually due to critical temperature)Off Off On Mains AC present, switch on. This PSU is providing power.Off Off Blinking AC power present, PSU in standby (other PSU is providing power).Blinking Blinking Off PSU firmware download in progress.Off On Off AC power missing, PSU in standby (other PSU is providing power).On On On Firmware has lost communication with the PSU module.On — Off PSU has failed. Follow procedure in “Replacing a PSU” (page 138).Table 18 FCM LED descriptionsLED Status/descriptionModuleOKConstant green indicates that the FCM is working correctly.Off indicates the fan module has failed. Follow procedure in “Replacing an FCM” (page 140).Fan Fault Amber indicates the fan module has failed. Follow procedure in “Replacing an FCM” (page 140).Table 19 Ops panel LED descriptionsLED Status/descriptionUnit ID Display Usually shows the ID number for the enclosure, but can be used for other purposes.Power On/Standby Amber if the system is in standby. Green if the system has full power.Module Fault Amber indicates a fault in a PSU, FCM, or IOM. Check the drawer LEDs for indication ofa disk fault. See also “Drawer LEDs” (page 101).Logical Status Amber indicates a fault from something other than firmware (usually a disk, an HBA, or aninternal or external RAID controller). Check the drawer LEDs for indication of a diskfault. See also “Drawer LEDs” (page 101).Drawer 0 Fault Amber is there is a disk, cable, or sideplane fault in drawer 0. Open the drawer and checkDDICs for faults.Drawer 1 Fault Amber is there is a disk, cable, or sideplane fault in drawer 1. Open the drawer and checkDDICs for faults.