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POWER7 information

PWR1904

A power supply fault is occurring on the +12V/-12V line.

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

Procedure for 8248-L4T, 8408-E8D, or 9109-RMD

  1. Perform the following steps:
    1. Power off the system.
    2. Replace one of the memory DIMMs on a memory riser card. See System FRU locations for information about FRU locations for the system that you are servicing.
    3. Power on the system. See Powering on and powering off the system.
    4. Has this resolved the problem?
      • No: Continue with step 1.e.
      • Yes: This ends the procedure.
    5. Have you replaced all of the DIMMs?
      • No: Repeat step 1 and replace the next memory DIMM.
      • Yes: Go to step 2.
  2. Perform the following steps:
    1. Power off the system and disconnect the ac power cable from the unit you are working on.
    2. Disconnect all of the I/O devices (tape, diskette, optical, and disk units) from the unit you are working on by sliding them partially out of the unit.
    3. Remove and label all cards (for example, PCI adapters, memory riser cards, GX adapters, RIO/HSL and RAID cards if installed).
    4. Reconnect the ac power cable to the unit you are working on.
    5. Power on the system.
    Does a power reference code occur?
    • Yes: Continue with the next step.
    • No: Go to step 7.
  3. Perform the following steps:
    1. Power off the system. See Powering on and powering off the system.
    2. Replace one of the system fans. See System FRU locations for information about FRU locations for the system that you are servicing.
    3. Power on the system.
    Does a power reference code occur?
    • Yes: Continue with the next step.
    • No: The fan you just replaced was the failing item.

      This ends the procedure.

  4. Have you tried replacing all of the fans?
    • Yes: Reinstall all of the fans you replaced in step 3 and continue with the next step.
    • No: Perform the following steps:
      1. Power off the system.
      2. Reinstall the fan that you just removed in step 3 to its original location.
      3. Repeat step 3.
  5. Perform the following steps:
    1. Power off the system.
    2. Replace one of the voltage regulator cards. See System FRU locations for the voltage regulator card location for the system you are servicing.
    3. Power on the system.

    Does a power reference code occur?

    • Yes: Continue with the next step.
    • No: The voltage regulator card you just replaced was the failing item.

      This ends the procedure.

  6. Have you tried replacing all of the voltage regulator cards?
    • Yes: Continue with the next step.
    • No: Perform the following steps:
      1. Power off the system. See Powering on and powering off the system.
      2. Reinstall the voltage regulator card that you just removed in step 6 to its original location.
      3. Repeat step 5.
  7. Perform the following steps:
    1. Power off the system. See Powering on and powering off the system.
    2. Reinstall all of the cards (PCI adapters, memory risers, GX adapters, RIO/HSL and RAID cards) you removed in step 2 to their original locations.
    3. Power on the system. See Powering on and powering off the system.

    Does a power reference code occur?

    • Yes: Continue with the next step.
    • No: Go to step 10.
  8. Perform the following steps:
    1. Power off the system. See Powering on and powering off the system.
    2. Disconnect one of the cards you reinstalled in step 7.
    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 System FRU locations ). This ends the procedure.
  9. Have you disconnected all of the cards?
    • No: Repeat step 8.
    • Yes: Reinstall all of the parts you have removed or exchanged in this procedure and perform problem analysis using the reference code. This ends the procedure.
  10. Perform the following steps:
    1. Power off the system. See Powering on and powering off the system.
    2. Reconnect all of the I/O devices (tape, diskette, optical, and disk units) that you disconnected in step 3.
    3. Power on the system. See Powering on and powering off the system.

    Does a power reference code occur?

    • Yes: Continue with the next step.
    • No: The problem has been resolved. This ends the procedure.
  11. Perform the following steps:
    1. Power off the system. See Powering on and powering off the system.
    2. Disconnect one of the I/O devices (tape, diskette, optical, and disk units) that you reconnected in step 10.
    3. Power on the system. See Powering on and powering off 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 (see System FRU locations). This ends the procedure.
  12. Have you tried disconnecting all of the I/O devices?
    • No: Repeat step 11.
    • Yes: Reinstall all of the parts you have removed or exchanged in this procedure and contact your next level of support. This ends the procedure.

Procedure for 8412-EAD, 9117-MMB, 9117-MMC, 9117-MMD, 9179-MHB, 9179-MHC, or 9179-MHD

  1. Perform the following steps:
    1. Power off the system.
    2. Replace one of the memory DIMMs on the processor card. See System FRU locations for information about FRU locations for the system that you are servicing.
    3. Power on the system. See Powering on and powering off the system.
    4. Has this resolved the problem?
      • No: Continue with step 1.e.
      • Yes: This ends the procedure.
    5. Have you replaced all of the DIMMs?
      • No: Repeat step 1 and replace the next memory DIMM.
      • Yes: Go to step 2.
  2. Perform the following steps:
    1. Power off the system. See Powering on and powering off the system.
    2. Replace the processor card. See System FRU locations for information about FRU locations for the system you are servicing.
    3. Power on the system.
    4. Has this resolved the problem?
      • No: Continue with the next step.
      • Yes: This ends the procedure.
  3. Perform the following steps:
    1. Power off the system and disconnect the ac power cable from the unit you are working on.
    2. Disconnect all of the I/O devices (tape, diskette, optical, and disk units) from the unit you are working on by sliding them partially out of the unit.
    3. Remove and label all cards (for example, PCI adapters, memory DIMMs, GX adapters, RIO/HSL and RAID cards if installed).
    4. Reconnect the ac power cable to the unit you are working on.
    5. Power on the system.

    Does a power reference code occur?

    • Yes: Continue with the next step.
    • No: Go to step 8.
  4. Perform the following steps:
    1. Power off the system. See Powering on and powering off the system.
    2. Replace one of the system fans. See System FRU locations for information about FRU locations for the system that you are servicing.
    3. Power on the system.

    Does a power reference code occur?

    • Yes: Continue with the next step.
    • No: The fan you just replaced was the failing item.

      This ends the procedure.

  5. Have you tried replacing all of the fans?
    • Yes: Reinstall all of the fans you replaced in step 4 and continue with the next step.
    • No: Perform the following steps:
      1. Power off the system.
      2. Reinstall the fan that you just removed in step 4 to its original location.
      3. Continue with the next step.
  6. Perform the following steps:
    1. Power off the system.
    2. Replace one of the voltage regulator cards. See System FRU locations for the voltage regulator card location for the system you are servicing.
    3. Power on the system.

    Does a power reference code occur?

    • Yes: Continue with the next step.
    • No: The voltage regulator card you just replaced was the failing item.

      This ends the procedure.

  7. Have you tried replacing all of the voltage regulator cards?
  8. Perform the following steps:
    1. Power off the system. See Powering on and powering off the system.
    2. Reinstall all of the cards (PCI adapters, memory DIMMs, GX adapters, RIO/HSL and RAID cards) you removed in step 3 to their original locations.
    3. Power on the system. See Powering on and powering off the system.

    Does a power reference code occur?

    • Yes: Continue with the next step.
    • No: Go to step 11.
  9. Perform the following steps:
    1. Power off the system. See Powering on and powering off the system.
    2. Disconnect one of the cards you reinstalled 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 System FRU locations). This ends the procedure.
  10. Have you disconnected all of the cards?
    • No: Repeat step 9.
    • Yes: Reinstall all of the parts you have removed or exchanged in this procedure and perform problem analysis using the reference code. This ends the procedure.
  11. Perform the following steps:
    1. Power off the system. See Powering on and powering off the system
    2. Reconnect all of the I/O devices (tape, diskette, optical, and disk units) that you disconnected in step 3.
    3. Power on the system. See Powering on and powering off the system

    Does a power reference code occur?

    • Yes: Continue with the next step.
    • No: The problem has been resolved. This ends the procedure.
  12. Perform the following steps:
    1. Power off the system. See Powering on and powering off the system
    2. Disconnect one of the I/O devices (tape, diskette, optical, and disk units) that you reconnected in step 11.
    3. Power on the system. See Powering on and powering off 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 (see System FRU locations). This ends the procedure.
  13. Have you tried disconnecting all of the I/O devices?
    • No: Repeat step 12.
    • Yes: Reinstall all of the parts you have removed or exchanged in this procedure and contact your next level of support.This ends the procedure.


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Last updated: Thu, July 23, 2015