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DTC P2101: Throttle Actuator "A" Control Motor Circuit Range/Performance: Notes

DTC detecting condition: 

Immediately at fault recognition

Trouble symptom: 

CAUTION: Use the check board when measuring the ECM terminal voltage and resistance. Ref. to ENGINE (DIAGNOSTICS) (H4DO)>General Description>PREPARATION TOOL>HOW TO USE CHECK BOARD .
NOTE: After the faulty parts are repaired or replaced, perform the final check in Basic Diagnostic Procedure. Ref. to ENGINE (DIAGNOSTICS) (H4DO)>Basic Diagnostic Procedure>PROCEDURE .

Wiring diagram: 

Engine Electrical System Ref. to WIRING SYSTEM (CROSSTREK MODEL)>Engine Electrical System>WIRING DIAGRAM .

G12399988Courtesy of SUBARU OF AMERICA, INC.
  1. CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL (SHORT TO GROUND)  .
    1. Turn the ignition switch to OFF.
    2. Disconnect the connector from ECM.
    3. Disconnect the connectors from electronic throttle control.
    4. Measure the resistance between ECM connector and chassis ground.

      Connector & terminal 

      (E158) No. 27 - Chassis ground:

      (E158) No. 29 - Chassis ground:

      (E158) No. 29 - (E158) No. 44:

      (E158) No. 43 - Chassis ground:

      (E158) No. 43 - (E158) No. 44:

    Is the resistance 1 MΩ or more?

    Yes:  Go to  2.

    No:  Repair the ground short circuit of harness between ECM connector and electronic throttle control connector.

  2. CHECK THE SHORT CIRCUIT INSIDE ECM (SHORT TO GROUND)  .
    1. Connect the connector to ECM.
    2. Measure the resistance between electronic throttle control connector and engine ground.

      Connector & terminal 

      (E57) No. 6 - Engine ground:

      (E57) No. 4 - Engine ground:

    Is the resistance 200 kΩ or more?

    Yes:  Go to  3.

    No:  Repair the ground short circuit of harness between ECM connector and electronic throttle control connector. Replace the ECM if defective. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DO)>ENGINE CONTROL MODULE (ECM) .

  3. CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL (OPEN)  .
    1. Disconnect the connector from ECM.
    2. Measure the resistance of harness between ECM connector and electronic throttle control connector.

      Connector & terminal 

      (E158) No. 29 - (E57) No. 6:

      (E158) No. 43 - (E57) No. 4:

      (E158) No. 30 - (E57) No. 3:

    Is the resistance less than 1 Ω?

    Yes:  Go to  4.

    No:  Repair the open circuit of harness between ECM connector and electronic throttle control connector.

  4. CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL (OPEN)  .
    1. Connect the connector to ECM.
    2. Measure the resistance between electronic throttle control connector and engine ground.

      Connector & terminal 

      (E57) No. 3 - Engine ground:

    Is the resistance less than 5 Ω?

    Yes:  Go to  5.

    No:  Repair the harness and connector.

    NOTE: In this case, repair the following item:
    • Open circuit of harness between ECM connector and engine ground
    • Poor contact of ECM connector
  5. CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL (SHORT TO POWER SUPPLY)  .
    1. Turn the ignition switch to ON.
    2. Measure the voltage between electronic throttle control connector and engine ground.

      Connector & terminal 

      (E57) No. 6 (+) - Engine ground (-):

      (E57) No. 4 (+) - Engine ground (-):

    Is the voltage 5 V or more?

    Yes:  Repair the short circuit to power in the harness between ECM connector and electronic throttle control connector.

    No:  Go to  6.

  6. CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL (SHORT BETWEEN LINES)  .
    1. Turn the ignition switch to OFF.
    2. Disconnect the connector from ECM.
    3. Measure the resistance between ECM connectors.

      Connector & terminal 

      (E158) No. 27 - (E158) No. 29:

      (E158) No. 27 - (E158) No. 43:

    Is the resistance 1 MΩ or more?

    Yes:  Go to  7.

    No:  Repair the short circuit between lines in harness between ECM connector and electronic throttle control connector.

  7. CHECK SENSOR OUTPUT  .
    1. Connect all connectors.
    2. Start the engine and warm up completely.
    3. Stop the engine, and then turn the ignition switch to ON (engine OFF).
    4. Using the Subaru Select Monitor, read the value in [Main-Throttle Sensor].

      Data Monitor 

      NOTE: For detailed operation procedures, refer to "Data Monitor". Ref. to ENGINE (DIAGNOSTICS) (H4DO)>DATA MONITOR .

    Is the value of [Main-Throttle Sensor] 0.81 - 0.87 V?

    Yes:  Go to  8.

    No:  Repair the poor contact of electronic throttle control connector. Replace the electronic throttle control if defective. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DO)>THROTTLE BODY .

  8. CHECK SENSOR OUTPUT  .

    Using the Subaru Select Monitor, read the value in [Sub-Throttle Sensor].

    Data Monitor 

    NOTE: For detailed operation procedures, refer to "Data Monitor". Ref. to ENGINE (DIAGNOSTICS) (H4DO)>DATA MONITOR .

    Is the value of [Sub-Throttle Sensor] 1.64 - 1.70 V?

    Yes:  Go to  9.

    No:  Repair the poor contact of electronic throttle control connector. Replace the electronic throttle control if defective. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DO)>THROTTLE BODY .

  9. CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL (OPEN)  .
    1. Turn the ignition switch to OFF.
    2. Disconnect the connector from ECM.
    3. Disconnect the connectors from electronic throttle control.
    4. Measure the resistance between ECM connector and electronic throttle control connector.

      Connector & terminal 

      (E158) No. 92 - (E57) No. 2:

      (E158) No. 83 - (E57) No. 1:

    Is the resistance less than 1 Ω?

    Yes:  Go to  10.

    No:  Repair the open circuit of harness between ECM connector and electronic throttle control connector.

  10. CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL (SHORT TO POWER SUPPLY)  .
    1. Connect the connector to ECM.
    2. Turn the ignition switch to ON.
    3. Measure the voltage between electronic throttle control connector and engine ground.

      Connector & terminal 

      (E57) No. 2 (+) - Engine ground (-):

      (E57) No. 1 (+) - Engine ground (-):

    Is the voltage 5 V or more?

    Yes:  Repair the short circuit to power in the harness between ECM connector and electronic throttle control connector.

    No:  Go to  11.

  11. CHECK HARNESS BETWEEN ECM AND ELECTRONIC THROTTLE CONTROL (SHORT TO GROUND)  .
    1. Turn the ignition switch to OFF.
    2. Disconnect the connector from ECM.
    3. Measure the resistance between electronic throttle control connector and engine ground.

      Connector & terminal 

      (E57) No. 2 - Engine ground:

      (E57) No. 1 - Engine ground:

    Is the resistance 1 MΩ or more?

    Yes:  Go to  12.

    No:  Repair the ground short circuit of harness between ECM connector and electronic throttle control connector.

  12. CHECK HARNESS FOR ELECTRONIC THROTTLE CONTROL CONNECTOR (SHORT BETWEEN LINES)  .

    Measure the resistance between electronic throttle control connectors.

    Connector & terminal 

    (E57) No. 2 - (E57) No. 1:

    Is the resistance 1 MΩ or more?

    Yes:  Go to  13.

    No:  Repair the short circuit in harness between ECM connector and electronic throttle control connector.

  13. CHECK ELECTRONIC THROTTLE CONTROL GROUND CIRCUIT (OPEN)  .

    Measure the resistance between ECM connector and chassis ground.

    Connector & terminal 

    (B134) No. 69 - Chassis ground:

    (B134) No. 70 - Chassis ground:

    (B134) No. 71 - Chassis ground:

    (B134) No. 72 - Chassis ground:

    Is the resistance less than 5 Ω?

    Yes:  Go to  14.

    No:  Repair the open circuit of harness between ECM connector and electronic throttle control connector.

  14. CHECK ELECTRONIC THROTTLE CONTROL  .

    Measure the resistance between electronic throttle control terminals.

    Terminals 

    No. 2 - No. 1:

    Is the resistance 50 Ω or less?

    Yes:  Go to  15.

    No:  Replace the electronic throttle control. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DO)>THROTTLE BODY .

  15. CHECK ELECTRONIC THROTTLE CONTROL  .

    Move the throttle valve to the fully opened and fully closed positions with fingers.

    Check that the valve returns to the specified position when releasing fingers.

    Does the valve return to the specified position? Standard value: 3 mm (0.12 in) from fully closed position

    Yes:  Repair the poor contact of ECM connector.

    No:  Replace the electronic throttle control. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DO)>THROTTLE BODY .

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