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Home >> Infiniti >> 2008 >> G35 Base >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control System - DTCS P0850 Through P2A03 >> DTC P1233, P2101: Electric Throttle Control Function >> Diagnosis Procedure
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Diagnosis Procedure

  1. CHECK GROUND CONNECTION
    1. Turn ignition switch OFF.
    2. Check ground connection M95. Refer to Ground Inspection in "CIRCUIT INSPECTION ".

    Is the inspection result normal? 

    YES: GO TO 2.

    NO: Repair or replace ground connection.

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

    Check the voltage between ECM harness connector and ground.

    TERMINALS VOLTAGE REFERENCE

    DTC ECM Ground Condition Voltage
    Connector Terminal
    P1233 F102 52 Ground Ignition switch OFF Approx. 0V
    Ignition switch ON Battery voltage
    P2101 F101 3 Ignition switch OFF Approx. 0V
    Ignition switch ON Battery voltage

    Is the inspection result normal? 

    YES: GO TO  9.

    NO: GO TO 3.

  3. 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 E7.
    4. Check the continuity between IPDM E/R harness connector and ECM harness connector.
      TERMINALS CONTINUITY REFERENCE

      IPDM E/R ECM Continuity
      Connector Terminal Connector Terminal
      E7 70 F101 25 Existed
    5. Also check harness for short to ground and short to power.

    Is the inspection result normal? 

    YES: GO TO  5.

    NO: GO TO 4.

  4. DETECT MALFUNCTIONING PART

    Check the following.

    • Harness connectors E3, F1
    • Harness connectors F104, F105
    • Harness for open or short between ECM and IPDM E/R

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

  5. CHECK THROTTLE CONTROL MOTOR RELAY INPUT SIGNAL CIRCUIT-II
    1. Check the continuity between IPDM E/R harness connector and ECM harness connector.
      TERMINALS CONTINUITY REFERENCE

      DTC IPDM E/R ECM Continuity
      Connector Terminal Connector Terminal
      P1233 E7 54 F102 52 Existed
      P2101 F101 3
    2. Also check harness for short to ground and short to power.

    Is the inspection result normal? 

    YES: GO TO  7.

    NO: GO TO 6.

  6. DETECT MALFUNCTIONING PART

    Check the following.

    • Harness connectors E3, F1
    • Harness for open or short between ECM and IPDM E/R

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

  7. CHECK FUSE
    1. Disconnect 15A fuse (No. 51) from IPDM E/R.
    2. Check 15A fuse for blown.

    Is the inspection result normal? 

    YES: GO TO 8.

    NO: Replace 15A fuse.

  8. CHECK INTERMITTENT INCIDENT

    Refer to "INTERMITTENT INCIDENT ".

    Is the inspection result normal? 

    YES: Replace IPDM E/R.

    NO: Repair or replace harness or connectors.

  9. 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.
      TERMINALS CONTINUITY REFERENCE

      DTC Electric throttle control actuator ECM Continuity
      Bank Connector Terminal Connector Terminal
      P1233 2 F27 5 F102 49 Existed
      50 Not existed
      6 49 Not existed
      50 Existed
      P2101 1 F6 1 F101 2 Existed
      4 Not existed
      2 2 Not existed
      4 Existed
    5. Also check harness for short to ground and short to power.

    Is the inspection result normal? 

    YES: GO TO 10.

    NO: Repair or replace.

  10. CHECK ELECTRIC THROTTLE CONTROL ACTUATOR VISUALLY
    1. Remove the intake air duct.
    2. Check if foreign matter is caught between the throttle valve (1) and the housing.

    Is the inspection result normal? 

    YES: GO TO 11.

    NO: Remove the foreign matter and clean the electric throttle control actuator inside.

    Fig 1: Checking If Foreign Matter Is Caught Between Throttle Valve And Housing
    G05207803Courtesy of NISSAN MOTOR CO., U.S.A.
  11. CHECK THROTTLE CONTROL MOTOR

    Refer to "COMPONENT INSPECTION ".

    Is the inspection result normal? 

    YES: GO TO 12.

    NO: GO TO  13.

  12. CHECK INTERMITTENT INCIDENT

    Refer to "INTERMITTENT INCIDENT ".

    Is the inspection result normal? 

    YES: GO TO 13.

    NO: Repair or replace harness or connectors.

  13. REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR
    1. Replace malfunction electric throttle control actuator.
    2. Go to "SPECIAL REPAIR REQUIREMENT ".

      INSPECTION END

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