PWR1909

Please see Power isolation procedures for important safety information before servicing the system.

Instructions for 5095, 0595, 5790, 5796, 7311-D11, 7311-D20 and 7314-G30

Refer to Locating FRUs for instructions for removing and replacing any FRUs called out by the following procedure.

1. Perform the following:
   1. Power off the system.
   2. Disconnect all the I/O devices (tape, diskette, optical, and disk units) from the expansion unit or I/O tower you are working on by sliding them partially out of the unit (see Physical Locations).
   3. Remove and label all cards installed in the PCI card area.
   4. Power on the system.

   Does a power reference code occur?

   • Yes: Continue with the next step.
   • No: Go to step 8.
2. Perform the following:
   1. Power off the system.
   2. Remove one of the fans from the expansion unit or I/O tower that you have not previously removed during this procedure.
      Note:
      Disregard a fan reference code if it occurs during this step.
   3. Power on the system.

   Does a power reference code occur?

   • Yes: Continue with the next step.
   • No: The fan you removed in this step is the failing item.

     This ends the procedure.

3. Have you removed all of the fans one at a time?
   • No: Perform the following:
     1. Power off the system.
     2. Reinstall the fan that you removed in step 2 into its original location.
     3. Repeat step 2.
   • Yes: Reinstall all of the fans and continue with the next step.
4. Perform the following:
   Note:
   If there are no DASD installed in this enclosure, go to step 6.
   1. Power off the system.
   2. Remove the I/O tower power supply cable, at the DASD backplane, that you have not previously removed.
   3. Power on the system.

   Does a power reference code occur?

   • No: The DASD backplane that was disconnected in this step is the failing item.

     This ends the procedure.

   • Yes: Continue with the next step.
5. Have you disconnected the power cables from each of the DASD backplanes one at a time?
   • Yes: Continue with the next step.
   • No: Repeat step 4.
6. Perform the following:
   1. Power off the system.
   2. Remove a power supply that you have not previously removed, and replace it with a new one.
   3. Power on the system.

   Does a power reference code occur?

   • Yes: Continue with the next step.
   • No: The power supply that was removed in this step is the failing item.

     This ends the procedure.

7. Have you removed all of the power supplies one at a time?
   • Yes: Perform the following:
     1. Remove the new power supply that you installed in step 6 and reinstall the original power supply.
     2. Replace the I/O backplane if you are working on a 7311-D11, 7314-G30, 5790 or 5796. Replace the tower backplane if you are working on a 5095 or 0595.

        This ends the procedure.

   • No: Remove the new power supply that you installed in step 6 and reinstall the original power supply. Then, repeat step 6.
8. Perform the following:
   1. Power off the system.
   2. Reinstall all of the cards you removed in step 1.
   3. Power on the system.

   Does a power reference code occur?

   • Yes: Continue with the next step.
   • No: Go to step 11.
9. Perform the following:
   1. Power off the system.
   2. Disconnect one of the cards you reconnected in step 8.
   3. Power on the system.

   Does a power reference code occur?

   • Yes: Continue with the next step.
   • No: Exchange the last card you disconnected in this step (see DUMMY PAGE FOR Part information) Reinstall all the parts.

     This ends the procedure.

10. Have you disconnected all the cards?
    • No: Repeat step 9.
    • Yes: Reinstall all the parts and return to Starting a Service Call.

      This ends the procedure.

11. Perform the following:
    1. Power off the system.
    2. Reconnect all of the I/O devices (tape, diskette, optical, or disk units) that you disconnected in step 1.
    3. Power on the system.

    Does a power reference code occur?

    • Yes: Continue with the next step.
    • No: This ends the procedure.
12. Perform the following:
    1. Power off the system.
    2. Disconnect one of the I/O devices you reconnected in step 11.
    3. Power on the system.

    Does a power reference code occur?

    • Yes: Continue with the next step.
    • No: Exchange the last I/O device you disconnected in this step.

      This ends the procedure.

13. Have you disconnected all of the I/O devices?
    • No: Repeat step 12.
    • Yes: Reinstall all the parts and return to Starting a Service Call.

      This ends the procedure.