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Home >> Infiniti >> 2012 >> QX56 AWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - DTCS P1550 To P2A03 >> DTC P2101: Electric Throttle Control Function >> Diagnosis Procedure
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Diagnosis Procedure

  1. CHECK THROTTLE CONTROL MOTOR RELAY INPUT SIGNAL CIRCUIT-I
    1. Check the voltage between ECM harness connector and ground under the following conditions.
      ECM Ground Condition Voltage
      Connector terminal
      E80 173 Ground Ignition switch: OFF Approx. 0 V
      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.
    4. Check the continuity between ECM harness connector and IPDM E/R harness connector.
      IPDM E/R ECM Continuity
      Connector Terminal Connector terminal
      E15 60 E80 123 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 or 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 ECM harness connector and IPDM E/R harness connector.
      IPDM E/R ECM Continuity
      Connector Terminal Connector terminal
      E15 55 E80 173 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 or short to ground or short to power in harness or connectors.

  6. CHECK FUSE
    1. Disconnect 20 A fuse (No. 64) from IPDM E/R.
    2. Check 20 A fuse for blown.

    Is the inspection result normal? 

    YES: GO TO 7.

    NO: Replace 20 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.
      Electric throttle control actuator ECM Continuity
      Connector Terminal Connector terminal
      F66 5 F110 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.

  9. CHECK ELECTRIC THROTTLE CONTROL ACTUATOR VISUALLY
    1. Remove the intake air duct.
    2. Check if 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, then perform throttle valve closed position learning. Refer to "WORK PROCEDURE ".

  10. CHECK THROTTLE CONTROL MOTOR

    Refer to "COMPONENT INSPECTION ".

    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
    1. Replace malfunction electric throttle control actuator. Refer to "REMOVAL AND INSTALLATION ".
    2. Perform "SPECIAL REPAIR REQUIREMENT ".

    : INSPECTION END