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DTC P0410: Secondary Air System: Notes

DTC detecting condition: 

Detected when two consecutive driving cycles with fault occur.

CAUTION: After servicing or replacing faulty parts, perform Clear Memory Mode Refer to ENGINE (DIAGNOSTICS) (STI)>CLEAR MEMORY MODE>OPERATION ., and inspection mode Refer to ENGINE (DIAGNOSTICS) (STI)>INSPECTION MODE>PROCEDURE .

Wiring diagram: 

Engine Electrical System Refer to WIRING SYSTEM>ENGINE ELECTRICAL SYSTEM>WIRING DIAGRAM .

G12456928Courtesy of SUBARU OF AMERICA, INC.
  1. CHECK SECONDARY AIR PUMP FUSE. 

    Check if the secondary air pump fuse (60 A) is blown out.

    Is the fuse blown out?

    Yes:  Go to  2.

    No:  Go to  3.

  2. CHECK HARNESS BETWEEN FUSE BOX AND SECONDARY AIR PUMP CONNECTOR. 
    1. Remove the secondary air pump fuse from the fuse box.
    2. Disconnect the secondary air pump connector.
    3. Measure the resistance between the secondary air pump fuse and secondary air pump connector, and chassis ground.

    Connector & terminal 

    (F9) No. 16 - Chassis ground:

    (F11) No. 2 - Chassis ground:

    Is the resistance 1 MΩ or more?

    Yes:  Replace the fuse with a new part, and connect the secondary air pump connector.

    Go to  3.

    No:  Repair ground short of the harness between the fuse box and the secondary air pump connector.

  3. CHECK SECONDARY AIR PUMP OPERATION. 
    CAUTION: Complete the inspection of secondary air pump operation in one try. This inspection will put a heavy workload on the secondary air pump, so the continuous operation may cause damage to the pump. Do not operate the pump continuously for more than three times. If you need to operate the pump further, turn the ignition switch to OFF and wait for at least two hours.
    1. Install the delivery mode fuse.
    2. Turn the ignition switch to ON.
    3. Perform operation check for the secondary air pump using the Subaru Select Monitor.
    NOTE:
    • Activation by the active test stops in 10 seconds in order to protect the secondary air pump.
    • When performing the active test again, disconnect the ground cable from battery, wait at least one minute, and perform the clear memory operation of ECM.
    • For detailed operation procedures, refer to the "Active Test". Refer to ENGINE (DIAGNOSTICS) (STI)>ACTIVE TEST .

    Does the secondary air pump operate?

    Yes:  Go to  4.

    No:  Go to  5.

  4. CHECK DUCT BETWEEN SECONDARY AIR PUMP AND COMBINATION VALVE. 

    Check the duct between secondary air pump and combination valve.

    Is there damage, clog or disconnection of the duct?

    Yes:  Replace, clean or connect the duct.

    No:  Replace the secondary air combination valve LH. Refer to EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) (STI)>SECONDARY AIR COMBINATION VALVE .

  5. CHECK POWER SUPPLY TO SECONDARY AIR PUMP. 
    1. Turn the ignition switch to OFF.
    2. Disconnect the battery negative terminal, wait for 1 minute, and connect it again.
    3. Disconnect the secondary air pump connector.
    4. Install the delivery mode fuse.
    5. Turn the ignition switch to ON.
    6. Using the Subaru Select Monitor, measure the voltage between the secondary air pump connector and chassis ground while the secondary air pump is operating.
    NOTE:
    • Activation by the active test stops in 10 seconds in order to protect the secondary air pump.
    • When performing the active test again, disconnect the ground cable from battery, wait at least one minute, and perform the clear memory operation of ECM.
    • For detailed operation procedures, refer to the "Active Test". Refer to ENGINE (DIAGNOSTICS) (STI)>ACTIVE TEST .

    Connector & terminal 

    (F11) No. 2 (+) - Chassis ground (-):

    Is the voltage 10 V or more?

    Yes:  Replace the secondary air pump. Refer to EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) (STI)>SECONDARY AIR PUMP .

    No:  Go to  6.

  6. CHECK HARNESS BETWEEN SECONDARY AIR PUMP RELAY AND SECONDARY AIR PUMP CONNECTOR. 
    1. Turn the ignition switch to OFF.
    2. Remove the secondary air pump relay.
    3. Measure the resistance of harness between secondary air pump relay connector and secondary air pump connector.

    Connector & terminal 

    (F9) No. 11 - (F11) No. 2:

    Is the resistance less than 1 Ω?

    Yes:  Go to  7.

    No:  Repair the open circuit in harness between secondary air pump relay connector and secondary air pump connector.

  7. CHECK HARNESS BETWEEN SECONDARY AIR PUMP CONNECTOR AND CHASSIS GROUND. 

    Measure the resistance of the harness between secondary air pump connector and chassis ground.

    Connector & terminal 

    (F11) No. 1 - Chassis ground:

    Is the resistance less than 5 Ω?

    Yes:  Go to  8.

    No:  Repair the open circuit of the harness between secondary air pump connector and chassis ground.

  8. CHECK SECONDARY AIR PUMP RELAY. 
    1. Connect the battery to terminals No. 12 and No. 13 of the secondary air pump relay.
    2. Measure the resistance between secondary air pump relay terminals.

    Terminals 

    No. 14 - No. 11:

    Is the resistance less than 1 Ω?

    Yes:  Go to  9.

    No:  Replace the secondary air pump relay. Refer to ENGINE (DIAGNOSTICS) (STI)>ELECTRICAL COMPONENT LOCATION .

  9. CHECK SECONDARY AIR PUMP RELAY POWER SUPPLY. 
    1. Turn the ignition switch to ON.
    2. Measure the voltage between the secondary air pump relay connector and chassis ground.

    Connector & terminal 

    (F9) No. 14 (+) - Chassis ground (-):

    (F9) No. 12 (+) - Chassis ground (-):

    Is the voltage 10 V or more?

    Yes:  Go to  10.

    No:  Repair the open or short to ground in the power supply circuit.

  10. CHECK HARNESS BETWEEN ECM AND SECONDARY AIR PUMP RELAY CONNECTOR. 
    1. Turn the ignition switch to OFF.
    2. Disconnect the ECM connector.
    3. Measure the resistance of harness between ECM connector and secondary air pump relay connector.

    Connector & terminal 

    (B135) No. 27 - (F9) No. 13:

    Is the resistance less than 1 Ω?

    Yes:  Repair the poor contact of ECM connector.

    No:  Repair the harness and connector.

    NOTE: In this case, repair the following item:
    • Open circuit in harness between ECM connector and secondary air pump relay connector
    • Poor contact of coupling connector
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