ECD SYSTEM, Diagnostic DTC:15 (4)

DTC Code DTC Name
15 (4) Throttle Motor Circuit Malfunction

DESCRIPTION

The throttle control motor is operated by the ECM and it opens and closes the throttle valve.

The fully open position of the throttle valve is detected by the throttle open switch mounted on the venturi.

If this DTC is stored, the ECM shuts down the power for the throttle control motor.

DTC No. DTC Detection Condition Trouble Area
15 (4) Open or short in throttle control motor circuit

  • Open or short in throttle control motor circuit

  • Throttle control motor

  • Throttle valve

  • Open or short in throttle open switch circuit

  • Throttle open switch

  • ECM
Open or short in throttle open switch circuit

WIRING DIAGRAM

A01DXIFE01

INSPECTION PROCEDURE

Tech Tips

Read freeze frame data using the intelligent tester. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air-fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction.

PROCEDURE


  1. INSPECT THROTTLE OPEN SWITCH


    1. A01E0IJ

      Disconnect the throttle open switch connector.

    2. Remove the venturi.

    3. Measure the resistance of the throttle open switch.

      Standard resistance
      Tester Connection Throttle Valve Condition Specified Condition
      1 - 2 Open Below 1 Ω
      1 - 2 Closed 10 kΩ or higher

      Tech Tips

      The throttle open switch is integrated with the venturi. If the throttle open switch needs to be replaced, the entire venturi must be replaced.


    NG

    REPLACE VENTURI

    OK

  2. CHECK WIRE HARNESS (THROTTLE OPEN SWITCH - ECM AND BODY GROUND)


    1. A01DZLTE03

      Disconnect the T28 throttle open switch connector.

    2. Disconnect the E22 ECM connector.

    3. Measure the resistance of the wire harness side connectors.

      Standard resistance
      Tester Connection Specified Condition
      T28-1 - Body ground Below 1 Ω
      E22-15 (THOP) - T28-2 Below 1 Ω
      E22-15 (THOP) - Body ground 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS AND CONNECTOR

    OK

  3. CHECK ECM (THROTTLE CONTROL MOTOR CIRCUIT)


    1. A01E0HKE04

      During engine racing, measure the waveform according to the value(s) in the table below.

      OK
      Tester Connection Specified Condition
      E23-10 (LU+A) - E23-13 (E01) Correct waveform is as shown
      E23-9 (LU-A) - E23-13 (E01) Correct waveform is as shown
      E23-8 (LU+B) - E23-13 (E01) Correct waveform is as shown
      E23-7 (LU-B) - E23-13 (E01) Correct waveform is as shown

    OK

    REPLACE ECM

    NG

  4. INSPECT THROTTLE CONTROL MOTOR


    1. A01DUXME03

      Disconnect the throttle control motor connector.

    2. Measure the resistance of the throttle control motor.

      Standard resistance
      Tester Connection Condition Specified Condition
      1 - 2 20°C (68°F) 18 to 22 Ω
      2 - 3 20°C (68°F) 18 to 22 Ω
      4 - 5 20°C (68°F) 18 to 22 Ω
      5 - 6 20°C (68°F) 18 to 22 Ω

      Tech Tips

      The throttle control motor is integrated with the venturi. If the throttle control motor needs to be replaced, the entire venturi must be replaced.


    NG

    REPLACE VENTURI

    OK

  5. CHECK WIRE HARNESS (THROTTLE CONTROL MOTOR - ECM)


    1. A01DZWGE03

      Disconnect the throttle control motor connector.

    2. Disconnect the E23 ECM connector.

    3. Measure the resistance of the wire harness side connectors.

      Standard resistance
      Tester Connection Specified Condition
      T25-6 - E23-10 (LU+A) Below 1 Ω
      T25-4 - E23-9 (LU-A) Below 1 Ω
      T25-3 - E23-8 (LU+B) Below 1 Ω
      T25-1 - E23-7 (LU-B) Below 1 Ω
      E23-10 (LU+A) - E23-13 (E01) 10 kΩ or higher
      E23-9 (LU-A) - E23-13 (E01) 10 kΩ or higher
      E23-8 (LU+B) - E23-13 (E01) 10 kΩ or higher
      E23-7 (LU-B) - E23-13 (E01) 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS AND CONNECTOR

    OK

    CHECK ECM POWER SOURCE CIRCUIT