SFI SYSTEM, Diagnostic DTC:P0418

DTC Code DTC Name
P0418 Secondary Air Injection System Control "A" Circuit

DESCRIPTION

Refer to DTC P0412 Click here.

DTC No. DTC Detection Condition Trouble Area
P0418

All conditions are met for 3 seconds or more while idling immediately after the engine is started (2 trip detection logic):


  • Secondary air injection system is not operating (the air pump and emission control valve are off).

  • Diagnostic signal from the air injection control driver has a duty cycle of 20% (this indicates an open in the air pump circuit).

  • Battery voltage is 8 V or higher.

  • Open in air pump drive circuit

  • Air pump assembly

  • Air injection control driver assembly

  • ECM
P0418

All conditions are met for 3 seconds or more while idling immediately after the engine is started (2 trip detection logic):


  • Secondary air injection system is operating (the air pump and emission control valve are on).

  • Diagnostic signal from the air injection control driver has a duty cycle of 20% (this indicates a short in the air pump circuit).

  • Battery voltage is 8 V or higher.

  • Short between air pump drive circuit and body ground

  • Air pump assembly

  • Air injection control driver assembly

  • ECM

MONITOR DESCRIPTION

This DTC indicates an open or short circuit in the circuit containing the air pump of the secondary air injection system. The air injection control driver performs diagnosis of the air pump assembly, emission control valve set and itself, and sends the results of this diagnosis to the ECM as a duty signal. When the ECM receives a signal indicating a malfunction in the air pump assembly, emission control valve set or air injection control driver assembly, it illuminates the MIL and stores a DTC.

WIRING DIAGRAM

Refer to DTC P0412 Click here.

INSPECTION PROCEDURE

Note

Inspect the fuses for circuits related to this system before performing the following inspection procedure.

Tech Tips


  • By using the GTS to perform the Secondary Air Injection Check operation in the System Check, the air-fuel ratio and the pressure in the secondary air injection system passage can be checked while the secondary air injection system is operating. This helps technicians to troubleshoot the system when it malfunctions.

  • Read freeze frame data using the GTS. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.

PROCEDURE


  1. CHECK HARNESS AND CONNECTOR (AIR PUMP ASSEMBLY - AIR INJECTION CONTROL DRIVER ASSEMBLY, BATTERY AND BODY GROUND)


    1. Disconnect the air pump assembly connector.

    2. Disconnect the air injection control driver assembly connector.

    3. Disconnect the cable from the positive (+) battery terminal.

    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      C139-2 - C60-2 (VP) Always Below 1 Ω
      C60-1 (BATT) - positive (+) battery terminal Always Below 1 Ω
      C139-4 - Body ground Always Below 1 Ω
      C139-2 or C60-2 (VP) - Body ground Always 10 kΩ or higher
      C60-1 (BATT) or positive (+) battery terminal - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  2. INSPECT AIR PUMP ASSEMBLY


    1. Inspect the air pump assembly Click here.


    NG

    REPLACE AIR PUMP ASSEMBLY Click here

    OK

    REPLACE AIR INJECTION CONTROL DRIVER ASSEMBLY Click here

  3. REPLACE AIR PUMP ASSEMBLY


    1. Replace the air pump assembly Click here.


    NEXT

  4. CHECK WHETHER DTC OUTPUT RECURS (DTC P0418)


    1. Start the engine and warm it up.

    2. Turn the ignition switch off.

    3. Connect the GTS to the DLC3.

    4. Turn the ignition switch to ON and turn the GTS on.

    5. Clear the DTCs (if stored) Click here.

    6. Enter the following menus: Powertrain / Engine and ECT / Utility / Secondary Air Injection Check / Automatic Mode.

    7. Start the engine after the GTS initialization is finished.

    8. Perform the System Check operation by pressing Next.

    9. After operating the secondary air injection system, perform the following to confirm the secondary air injection system pending codes: Press the Exit button.

    10. Check for pending DTCs.

      OK
      No pending DTC is output.

    11. Turn the ignition switch off.

      Note


      • When performing the Secondary Air Injection Check operation after the battery cable has been reconnected, wait for 7 minutes with the ignition switch turned to ON or the engine running.

      • Turn the ignition switch off when the Secondary Air Injection Check operation finishes.


    NG

    REPLACE AIR INJECTION CONTROL DRIVER ASSEMBLY Click here

    OK

    END