Cannot power off system or SPCN-controlled I/O expansion unit

Use this procedure to analyze a failure of the normal command and control panel procedures to power off the system unit or an SPCN-controlled I/O expansion unit.

Attention: To prevent loss of data, ask the customer to verify that no interactive jobs are running before you perform this procedure.
For important safety information before continuing with this procedure, see Power isolation procedures.
  1. Is the power off problem on the system unit?
    • No: Continue with the next step.
    • Yes: Go to step 3.
  2. Ensure that the SPCN cables that connect the units are connected and seated correctly at both ends. Does the I/O unit power off, and is the power indicator light blinking slowly?
    • Yes: This ends the procedure.
    • No: Go to step 7.
  3. Attempt to power off the system. Does the system unit power off, and is the power indicator light blinking slowly?
    • No: Continue with the next step.
    • Yes: The system is not responding to normal power off procedures which could indicate a Licensed Internal Code problem. Contact your next level of support. This ends the procedure.
  4. Attempt to power off the system using ASMI. Does the system power off?
    • Yes: The system is not responding to normal power off procedures which could indicate a Licensed Internal Code problem. Contact your next level of support. This ends the procedure.
    • No: Continue with the next step.
  5. Attempt to power off the system using the control panel power button. Does the system power off?
    • Yes: Continue with the next step.
    • No: Go to step 10.
  6. Is there a reference code logged in either ASMI, the control panel, or the HMC that indicates a power problem?
    • Yes: Perform problem analysis for the reference code in the log. This ends the procedure.
    • No: Contact your next level of support. This ends the procedure.
  7. Is the I/O expansion unit that will not power off part of a shared I/O tower loop?
    • Yes: Go to step 9.
    • No: Continue with the next step.
  8. Attempt to power off the I/O expansion unit. Were you able to power off the expansion unit?
    • Yes: This ends the procedure.
    • No: Go to step 10.
  9. The unit will only power off under certain conditions:
    • If the unit is in private mode, it should power off with the system unit that is connected by the SPCN frame-to-frame cable.
    • If the unit is in switchable mode, it should power off if the "owning" system is powered off or is powering off, and the system unit that is connected by the SPCN frame-to-frame cable is powered off or is powering off.

    Does the I/O expansion unit power off?

    • No: Continue with the next step.
    • Yes: This ends the procedure.
  10. Ensure there are no jobs running on the system or partition, and verify that an uninterruptible power supply (UPS) is not powering the system or I/O expansion unit. Then continue with the next step.
  11. Perform the following:
    1. Remove the system or I/O expansion unit ac power cord from the external UPS or, if an external UPS is not installed, from the customer's ac power outlet. If the system or I/O expansion unit has more than one ac line cord, disconnect all the ac line cords.
    2. Exchange the following FRUs one at a time. See System FRU locations and System parts for information on FRU locations and parts for the system that you are servicing.

      If the system unit is failing:

      1. Power supply (Un-E1 or Un-E2). Go to step 12
      2. For 8203-E4A, 9407-M15, 9408-M25, (8204-E8A, and 9409-M5,0 exchange the system backplane (Un-P1). For 8234-EMA, 8234-EMA, 9117-MMA, and 9406-MMA exchange the service processor (Un-P1-C10). If that does not resolve the problem, exchange the I/O backplane (Un-P1).
      3. System control panel (Un-D1)

      If an I/O expansion unit is failing:

      1. Each power supply. Go to step 12
      2. I/O backplane
      3. I/O backplane in the unit preceding the unit that will not power off
      4. SPCN frame-to-frame cable

      This ends the procedure.

  12. A power supply might be the failing item.
    Attention: When replacing a redundant power supply, a 1xxx 1504, 1514, 1524, or 1534 reference code may be logged in the error log. If you just removed and replaced the power supply in the location associated with this reference code, and the power supply came ready after the install, disregard this reference code. If you had not previously removed and replaced a power supply, the power supply did not come ready after installation, or there are repeated fan fault errors after the power supply replacement, continue to follow these steps.

    Is the reference code 1xxx-15xx?

    • No: Continue with the next step.
    • Yes: Perform the following:
    1. Find the unit reference code in one of the following tables to determine the failing power supply.
    2. Ensure that the power cables are properly connected and seated.
    3. Is the reference code 1xxx-1500, 1510, 1520, or 1530 and is the failing unit configured with a redundant power supply option (or dual line cord feature)?
      • Yes: Perform PWR1911 before replacing parts.
      • No: Continue with step 12.d
    4. Refer to System FRU locations for information on FRU locations for the system that you are servicing.
    5. Replace the failing power supply (see the following tables to determine which power supply to replace).
    6. If the new power supply does not fix the problem, perform the following :
      1. Reinstall the original power supply.
      2. Try the new power supply in each of the other positions listed in the table.
      3. If the problem still is not fixed, reinstall the original power supply and go to the next FRU in the list.
      4. For reference codes 1xxx-1500, 1510, 1520, and 1530, exchange the power distribution backplane if a problem persists after replacing the power supply.
    Table 1. System Unit
    Unit Reference Code Power Supply
    1510, 1511, 1512, 1513, 1514, 7110 E1
    1520, 1521, 1522, 1523, 1524, 7120 E2
    Attention: For reference codes 1500, 1510, 1520, and 1530, perform PWR1911 before replacing parts.
    Table 2. 5088, 0588 expansion units
    Unit Reference Code Power Supply
    1510, 1511, 1512, 1513, 1514, 1516 P02
    1520, 1521, 1522, 1523, 1524, 1526 P01
    Attention: On a dual line cord system, for reference codes 1500, 1510, 1520, and 1530, perform PWR1911 before replacing parts. On a single line cord system, check the ac jumper to the power supply before replacing parts.
    Table 3. 5094, 5294 I/O expansion units (single line cord)
    Unit Reference Code Power Supply
    1510, 1511, 1512, 1513, 1514, 1516 P01
    1520, 1521, 1522, 1523, 1524, 1526 P02
    1530, 1531, 1532, 1533, 1534, 1536 P03
    Attention: On a dual line cord system, for reference codes 1500, 1510, 1520, and 1530, perform PWR1911 before replacing parts. On a single line cord system, check the ac jumper to the power supply before replacing parts.
    Attention: For 5094, 5294 expansion units, do not install power supplies P00 and P01 ac jumper cables on the same ac input module.
    Table 4. 5094, 5294 I/O expansion units (dual line cord)
    Unit Reference Code Power Supply
    1500, 1501, 1502, 1503 P00
    1510, 1511, 1512, 1513, 1514, 1516 P01
    1520, 1521, 1522, 1523, 1524, 1526 P02
    1530, 1531, 1532, 1533 P03
    Table 5. 5095, 0595, 5790, 7311-D11, 7311-D20, 7314-G30 expansion units
    Unit Reference Code Power Supply
    1510, 1511, 1512, 1513, 1514, 1516, 1517 P01/E1
    1520, 1521, 1522, 1523, 1524, 1526, 1527 P02/E2
    This ends the procedure.
  13. Is the reference code 1xxx-2600, 2603, 2605, or 2606?
    • No: Continue with the next step.
    • Yes: Perform the following:
    1. Refer to System FRU locations for information on FRU locations for the system you are servicing.
    2. Replace the failing power supply.
    3. Perform the following if the new power supply does not fix the problem:
      1. Reinstall the original power supply.
      2. Try the new power supply in each of the other positions listed in the table.
      3. If the problem still is not fixed, reinstall the original power supply and go to the next FRU in the list.
      Attention: Do not install power supplies P00 and P01 ac jumper cables on the same ac input module.
      Table 6. Failing power supplies
      System or Feature Code Failing Power Supply
      System unit Un-E1, Un-E2
      5094, 5294 (single line cord) P01, P02, P03
      5094, 5294 (dual line cord) P00, P01, P02, P03
      5088, 0588 P02, P01
      5095, 0595 P01, P02
      5790, 7311-D11, 7311-D20, 7314-G30 E1, E2
      This ends the procedure.
  14. Is the reference code 1xxx 8455 or 8456?
    • No: Return to Start of Call . This ends the procedure.
    • Yes: One of the power supplies is missing, and must be installed. Use the following table to determine which power supply is missing, and install the power supply. See System FRU locations for information on FRU location for the system you are servicing.
    Table 7. Missing power supplies
    Reference Code Missing Power Supply
    1xxx 8455 Un-E1
    1xxx 8456 Un-E2
    This ends the procedure.