Light path diagnostics LEDs descriptionThis topic provides a description of the light path diagnostics LEDs.The following table describes the server LEDs to help you detect the location of theproblems. For the location of the server LEDs, see “Storage book LEDs” on page161, “Compute book LEDs” on page 162, “DIMMs and microprocessor LEDs” onpage 163, “Half-length I/O book LEDs” on page 164, “Full-length I/O book LEDs”on page 164, “Standard I/O book LEDs” on page 165, and “Power-supply LEDs”on page 165.Note: Check the IMM event log or the system-event log for additional informationbefore you replace a FRU. See Chapter 5, “Parts listing, System x3850 X6 and x3950X6 Types 3837 and 3839,” on page 205, to determine which components arecustomer replaceable units (CRU) and which components are field replaceableunits (FRU).Table 36. Light path diagnostics LEDs descriptionLED Description3V battery error LED When this LED is lit, it indicates that a standard I/O book batteryerror has occurredAC power LED Each hot-swap power supply has an ac power LED and a dc powerLED. When the ac power LED is lit, it indicates that sufficient poweris being supplied to the power supply through the power cord.During normal operation, both the ac and dc power LEDs are litBoard error LED When this yellow LED is lit, it indicates that the book board errorhas occurred.Check log LED When this LED is lit (yellow), it indicates that there are errors thatrequire further diagnosis. Check the IMM event log for additionalinformation. See “Event logs” on page 168 for more informationabout event logs.DC power LED Each hot-swap power supply has a dc power LED and an ac powerLED. When the dc power LED is lit, it indicates that the powersupply is supplying adequate dc power to the system. Duringnormal operation, both the ac and dc power LEDs are litDIMM error LED When this LED is lit, it indicates that a memory error has occurred .Drive activity LEDs These LEDs are on SAS or SATA hard disk drives and solid statedrives. Each hot-swap drive has an activity LED, and when this LEDis flashing, it indicates that the drive is in use. When this LED issolid, it indicates that the drive is powered on but not in use.Drive status LEDs These LEDs are on SAS or SATA hard disk drives and solid statedrives. When one of these LEDs is lit, it indicates that the drive hasfailed. When this LED is flashing slowly (one flash per second), itindicates that the drive is being rebuilt. When the LED is flashingrapidly (three flashes per second), it indicates that the controller isidentifying the drive.Ethernet activity LED When these LEDs are lit, they indicate that the server is transmittingto or receiving signals from the Ethernet LAN that is connected tothe Ethernet port.Ethernet link LEDs When these LEDs are lit, they indicate that there is an active linkconnection on the 100BASE-TX, 1000BASE-TX, or 10GBASE-TXinterface for the Ethernet port.Fan error LED When this LED is lit, it indicates that a fan has failed, is operatingtoo slowly, or has been removed.Chapter 4. Troubleshooting 167
