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Home >> Infiniti >> 2013 >> M56 Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - DTCS P1087 To P2542 >> DTC P1233, P2101: Electric Throttle Control Function >> Diagnosis Procedure
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Diagnosis Procedure

  1. CHECK THROTTLE CONTROL MOTOR RELAY INPUT SIGNAL CIRCUIT-I 

    Check the voltage between ECM harness connector terminals as per the following.

    DTC ECM Condition Voltage (V)
    + -
    Connector Terminal Connector Terminal
    P1233 M160 173 M160 175 Ignition switch OFF Approx. 0
    P2101 Ignition switch ON Battery voltage

    Is the inspection result normal? 

    YES: GO TO  8.

    NO: GO TO 2.

  2. CHECK THROTTLE CONTROL MOTOR RELAY POWER SUPPLY CIRCUIT 
    1. Turn ignition switch OFF.
    2. Disconnect ECM harness connector.
    3. Disconnect IPDM E/R harness connector E5.
    4. Check the continuity between IPDM E/R harness connector and ECM harness connector.
      IPDM E/R ECM Continuity
      Connector Terminal Connector Terminal
      E5 7 M160 173 Existed
    5. Also check harness for short to ground and short to power.

      Is the inspection result normal? 

      YES: GO TO  4.

      NO: GO TO 3.

  3. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness for open or short between ECM and IPDM E/R
    • Loose or poor connection for each connector and harness

      : Repair open circuit, short to ground or short to power in harness or connectors.

  4. CHECK THROTTLE CONTROL MOTOR RELAY INPUT SIGNAL CIRCUIT-II 
    1. Check the continuity between IPDM E/R harness connector and ECM harness connector.
      DTC IPDM E/R ECM Continuity
      Connector Terminal Connector Terminal
      P1233
      P2101
      E7 71 M160 123 Existed
    2. Also check harness for short to ground and short to power.

      Is the inspection result normal? 

      YES: GO TO  6.

      NO: GO TO 5.

  5. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness for open or short between ECM and IPDM E/R
    • Loose or poor connection for each connector and harness

      : Repair open circuit, short to ground or short to power in harness or connectors.

  6. CHECK FUSE 
    1. Disconnect 15 A fuse (No. 50) from IPDM E/R.
    2. Check if 15 A fuse is blown.

      Is the inspection result normal? 

      YES: GO TO 7.

      NO: Replace 15 A fuse.

  7. CHECK INTERMITTENT INCIDENT 

    Refer to "INTERMITTENT INCIDENT ".

    Is the inspection result normal? 

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

    NO: Repair or replace harness or connectors.

  8. CHECK THROTTLE CONTROL MOTOR OUTPUT SIGNAL CIRCUIT FOR OPEN OR SHORT 
    1. Turn ignition switch OFF.
    2. Disconnect electric throttle control actuator harness connector.
    3. Disconnect ECM harness connector.
    4. Check the continuity between electric throttle control actuator harness connector and ECM harness connector.
      DTC Electric throttle control actuator ECM Continuity
      Bank Connector Terminal Connector Terminal
      P1233 2 F64 5 F111 62 Not existed
      58 Existed
      6 62 Existed
      58 Not existed
      P2101 1 F66 5 F111 57 Not existed
      63 Existed
      6 57 Existed
      63 Not existed
    5. Also check harness for short to ground and short to power.

      Is the inspection result normal? 

      YES: GO TO 9.

      NO: Repair or replace malfunctioning part.

  9. CHECK ELECTRIC THROTTLE CONTROL ACTUATOR VISUALLY 
    1. Remove the intake air duct. Refer to "EXPLODED VIEW ".
    2. Check that no foreign matter is caught between the throttle valve and the housing.

      Is the inspection result normal? 

      YES: GO TO 10.

      NO: Remove the foreign matter and clean the electric throttle control actuator inside, and then perform throttle valve closed position learning. Refer to "WORK PROCEDURE ".

  10. CHECK THROTTLE CONTROL MOTOR 

    Refer to "COMPONENT INSPECTION (ELECTRIC THROTTLE CONTROL MOTOR) ".

    Is the inspection result normal? 

    YES: GO TO 11.

    NO: GO TO  12.

  11. CHECK INTERMITTENT INCIDENT 

    Refer to "INTERMITTENT INCIDENT ".

    Is the inspection result normal? 

    YES: GO TO 12.

    NO: Repair or replace harness or connectors.

  12. REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR 

    Replace malfunction electric throttle control actuator. Refer to "REMOVAL AND INSTALLATION ".

    : INSPECTION END