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Diagnostic Procedure

DIAGNOSTIC PROCEDURE

Step Check Yes No
1 CHECK HARNESS BETWEEN ECM AND ACCELERATOR PEDAL POSITION SENSOR CONNECTOR. 
  1. Turn the ignition switch to OFF.
  2. Disconnect the connectors from ECM and accelerator pedal position sensor.
  3. Measure the resistance of harness between ECM and accelerator pedal position sensor connector.

    Connector & terminal 

    (B135) No. 23 - (B315) No. 6: 

    (B135) No. 29 - (B315) No. 5: 

Is the resistance less than 1 Ω? Go to step . Repair the open circuit in harness between ECM and accelerator pedal position sensor connector.
2 CHECK HARNESS BETWEEN ECM AND ACCELERATOR PEDAL POSITION SENSOR CONNECTOR. 
  1. Connect the connector to ECM.
  2. Measure the resistance between accelerator pedal position sensor connector and chassis ground.

    Connector & terminal 

    (B315) No. 5 - Chassis ground: 

Is the resistance less than 5 Ω? Go to step . Repair the harness and connector.
NOTE: In this case, repair the following item:
  • Open circuit of harness between ECM and engine ground
  • Poor contact of ECM connector
  • Poor contact of coupling connector
3 CHECK HARNESS BETWEEN ECM AND ACCELERATOR PEDAL POSITION SENSOR CONNECTOR. 
  1. Turn the ignition switch to ON.
  2. Measure the voltage between accelerator pedal position sensor connector and chassis ground.

    Connector & terminal 

    (B315) No. 6 (+) - Chassis ground (-): 

Is the voltage 5 V or more? Repair the short circuit to power supply in the harness between the ECM and accelerator pedal position sensor connector. Go to step .
4 CHECK HARNESS BETWEEN ECM AND ACCELERATOR PEDAL POSITION SENSOR CONNECTOR. 
  1. Turn the ignition switch to OFF.
  2. Disconnect the connector from ECM.
  3. Measure the resistance between ECM connectors.

    Connector & terminal 

    (B135) No. 21 - (B135) No. 23: 

Is the resistance 1 MΩ or more? Repair the poor contact of accelerator pedal position sensor connector. Replace the accelerator pedal if defective. Refer to ACCELERATOR PEDAL . > Repair the short circuit to power supply in the harness between the ECM and accelerator pedal position sensor connector.