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Diagnosis Procedure

  1. CHECK FUSE 

    Check that the following fuse is not fusing.

    Location Fuse No. Capacity
    IPDM E/R #51 15A
    #42 10A

    Is the fuse fusing? 

    YES: Replace the fuse after repairing the applicable circuit.

    NO: GO TO 2.

  2. CHECK GROUND CONNECTION 
    1. Check ground connection M11 and M95. Refer to "MAIN HARNESS ".

      Is the inspection result normal? 

      YES: GO TO 3.

      NO: Repair or replace ground connection.

  3. CHECK ECM GROUND CIRCUIT 
    1. Disconnect ECM harness connector.
    2. Check the continuity between ECM harness connector and ground.
      ECM Ground Continuity
      Connector Terminal
      F110 5 Ground Existed
      10
      M160 114
      115
      174
      175
    3. Also check harness for short to power.

      Is the inspection result normal? 

      YES: GO TO 4.

      NO: Repair open circuit in harness or connectors.

  4. CHECK ECM POWER SUPPLY (MAIN)-1 
    1. Reconnect ECM harness connector.
    2. Turn ignition switch ON.
    3. Check the voltage between ECM harness connector and ground.
      ECM Voltage (Approx.)
      + -
      Connector Terminal Connector Terminal
      M160 171 M160 175 Battery voltage
      172

      Is the inspection result normal? 

      YES: GO TO  6.

      NO: GO TO 5.

  5. CHECK ECM POWER SUPPLY (MAIN) CIRCUIT 
    1. Turn ignition switch OFF.
    2. Disconnect ECM harness connector and IPDM E/R harness connector.
    3. Check the continuity between ECM harness connector and IPDM E/R harness connector.
      ECM IPDM E/R Continuity
      Connector Terminal Connector Terminal
      M160 171 E5 6 Existed
      172

      Is the inspection result normal? 

      YES: Replace IPDM E/R. Refer to "REMOVAL AND INSTALLATION ".

      NO: Repair harness or connectors.

  6. CHECK ECM POWER SUPPLY (MAIN)-2 
    1. Turn ignition switch OFF and wait at least 10 seconds.
    2. Check the voltage between ECM harness connector terminals as per the following.
      ECM Condition Voltage (Approx.)
      + -
      Connector Terminal Connector Terminal
      M160 171 M160 175 After turning ignition switch OFF, battery voltage will exist for a few seconds Drop to 0 V.
      172

      Is the inspection result normal? 

      YES: GO TO  9.

      NO: GO TO 7.

  7. CHECK ECM RELAY CONTROL SIGNAL 
    1. Check the voltage between ECM harness connector terminals as per the following.
      ECM Condition Voltage (Approx.)
      + -
      Connector Terminal Connector Terminal
      M160 163 M160 175 Ignition switch ON 0 V
      Turn ignition switch OFF and wait at least 10 seconds. Battery voltage

      Is the inspection result normal? 

      YES: Check intermittent incident. Refer to "INTERMITTENT INCIDENT ".

      NO: GO TO 8.

  8. CHECK ECM RELAY CONTROL CIRCUIT 
    1. Disconnect ECM harness connector.
    2. Disconnect IPDM E/R harness connector.
    3. Check the continuity between ECM harness connector and IPDM E/R harness connector.
      ECM IPDM E/R Continuity
      Connector Terminal Connector Terminal
      M160 163 E7 70 Existed
    4. Also check harness for short to ground and short to power.

      Is the inspection result normal? 

      YES: Replace IPDM E/R. Refer to "REMOVAL AND INSTALLATION ".

      NO: Repair harness or connectors.

  9. CHECK IGNITION SWITCH SIGNAL 
    1. Reconnect ECM harness connector.
    2. Turn ignition switch ON.
    3. Check the voltage between ECM harness connector terminals.
      ECM Condition Voltage (Approx.)
      + -
      Connector Terminal Connector Terminal
      M160 141 M160 175 Ignition switch OFF 0 V
      Ignition switch ON Battery voltage

      Is the inspection result normal? 

      YES: GO TO  11.

      NO: GO TO 10.

  10. CHECK IGNITION SWITCH SIGNAL CIRCUIT 
    1. Disconnect ECM harness connector.
    2. Disconnect IPDM E/R harness connector.
    3. Check the continuity between ECM harness connector and IPDM E/R harness connector.
      ECM IPDM E/R Continuity
      Connector Terminal Connector Terminal
      M160 141 E7 52 Existed
    4. Also check harness for short to ground and short to power.

      Is the inspection result normal? 

      YES: Replace IPDM E/R. Refer to "REMOVAL AND INSTALLATION ".

      NO: Repair harness or connectors.

  11. CHECK ECM POWER SUPPLY (BACK-UP) 
    1. Reconnect ECM harness connector.
    2. Turn ignition switch OFF.
    3. Check the voltage between ECM harness connector terminals.
      ECM Voltage (Approx.)
      + -
      Connector Terminal Connector Terminal
      M160 156 M160 175 Battery voltage

      Is the inspection result normal? 

      YES: INSPECTION END

      NO: GO TO 12.

  12. CHECK ECM POWER SUPPLY (BACK-UP) CIRCUIT 
    1. Disconnect ECM harness connector.
    2. Disconnect IPDM E/R harness connector.
    3. Check the continuity between ECM harness connector and IPDM E/R harness connector.
      ECM IPDM E/R Continuity
      Connector Terminal Connector Terminal
      M160 156 E5 10 Existed
    4. Also check harness for short to ground and short to power.

      Is the inspection result normal? 

      YES: Replace IPDM E/R. Refer to "REMOVAL AND INSTALLATION ".

      NO: Repair harness or connectors.

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