v Follow the suggested actions in the order in which they are listed in the Action column until the problemis solved.v See Chapter 3, “Parts listing, Type 7978 and 1913 server,” on page 89 to determine which components arecustomer replaceable units (CRU) and which components are field replaceable units (FRU).v If an action step is preceded by “(Trained service technician only),” that step must be performed only by atrained service technician.Symptom ActionThe server does not start. Check the four 12-volt power LEDs (A, B, C, and D) on the system board. See“Internal LEDs, connectors, and jumpers” on page 9 for the LED locations.1. If the Channel A power LED is lit, check components in the following order.a. Remove all PCI adapters and riser cards. Try restarting the server. If theserver starts, reinstall the PCI adapters and riser cards, one at a time, toisolate the defective adapter.b. (Trained service technician only) System boardc. (Trained service technician only) Power backplane.2. If the Channel B power LED is lit, check components in the order listed below.a. Fans 1 and 2b. (Trained service technician only) Remove microprocessor 2 (if present). Tryrestarting the server.c. (Trained service technician only) System boardd. (Trained service technician only) Power backplane3. If the Channel C power LED is lit, check components in the following order.a. Fans 3 and 4b. (Trained service technician only) System boardc. (Trained service technician only) Power backplaned. (Trained service technician only) Microprocessor 14. If the Channel D power LED is lit, check components in the following order.a. Remove all DIMMs. Try restarting the server, listening for any memory errorbeep codes. If the server restarts, reinstall the DIMMs, one pair at a time, toisolate the defective DIMM (see “Installing a memory module” on page 110).b. Fans 5 and 6c. (Trained service technician only) System boardd. (Trained service technician only) Power backplaneThe server does not turn off. 1. Determine whether you are using an Advanced Configuration and PowerInterface (ACPI) or a non-ACPI operating system. If you are using a non-ACPIoperating system, complete the following steps:a. Press Ctrl+Alt+Delete.b. Turn off the server by pressing the power-control button for 5 seconds.c. Restart the server.d. If the server fails POST and the power-control button does not work,disconnect the ac power cord for 20 seconds; then, reconnect the ac powercord and restart the server.The server unexpectedly shutsdown, and the LEDs on theoperator information panel arenot lit.See “Solving undetermined problems” on page 86.Chapter 2. Diagnostics 53
