TOYOTA PARKING ASSIST-SENSOR SYSTEM (for 8 Sensor Type), Diagnostic DTC:C1AEC

DTC Code DTC Name
C1AEC Front Sensor Communication Circuit

DESCRIPTION

This DTC is stored when there is an open or short circuit in the communication line between the front sensors and ECU, or when there is a malfunction in a front sensor.

DTC Code DTC Detection Condition Trouble Area
C1AEC An open or short circuit in the communication line between the front sensors and ECU or a malfunction in a front sensor during initialization mode after the ignition switch is turned to ON.

  • Front ultrasonic sensor circuit

  • Clearance warning ECU*1

  • Parking assist ECU*2

WIRING DIAGRAM

A00JVL7E01

INSPECTION PROCEDURE

PROCEDURE


  1. CHECK FOR DTC (C1AEC)


    1. Clear the DTCs Click here.

    2. Recheck for DTCs Click here.

      Result
      Result Proceed to
      DTC C1AEC is output (w/o Parking Assist Monitor System and/or Side Monitor System) A
      DTC C1AEC is output (w/ Parking Assist Monitor System and/or Side Monitor System) B
      No DTC is output C

    B

    CHECK HARNESS AND CONNECTOR (PARKING ASSIST ECU - FRONT CORNER SENSOR LH) Click here

    C

    USE SIMULATION METHOD TO CHECK Click here

    A

  2. CHECK HARNESS AND CONNECTOR (CLEARANCE WARNING ECU - FRONT CORNER SENSOR LH)


    1. Disconnect the I1 clearance warning ECU connector.

    2. Disconnect the B1 No. 1 ultrasonic sensor (front corner sensor LH) connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      I1-21 (BOF) - B1-1 (BI) Always Below 1 Ω
      I1-9 (SOF) - B1-3 (SI) Always Below 1 Ω
      I1-19 (E1) - B1-5 (EI) Always Below 1 Ω
      I1-21 (BOF) - Body ground Always 10 kΩ or higher
      I1-9 (SOF) - Body ground Always 10 kΩ or higher
      I1-19 (E1) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. CHECK HARNESS AND CONNECTOR (FRONT CORNER SENSOR LH - FRONT CENTER SENSOR LH)


    1. Disconnect the B1 No. 1 ultrasonic sensor (front corner sensor LH) connector.

    2. Disconnect the B2 No. 1 ultrasonic sensor (front center sensor LH) connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      B1-2 (BO) - B2-1 (BI) Always Below 1 Ω
      B1-4 (SO) - B2-3 (SI) Always Below 1 Ω
      B1-6 (EO) - B2-5 (EI) Always Below 1 Ω
      B1-2 (BO) - Body ground Always 10 kΩ or higher
      B1-4 (SO) - Body ground Always 10 kΩ or higher
      B1-6 (EO) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK HARNESS AND CONNECTOR (FRONT CENTER SENSOR LH - FRONT CENTER SENSOR RH)


    1. Disconnect the B2 No. 1 ultrasonic sensor (front center sensor LH) connector.

    2. Disconnect the B3 No. 1 ultrasonic sensor (front center sensor RH) connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      B2-2 (BO) - B3-1 (BI) Always Below 1 Ω
      B2-4 (SO) - B3-3 (SI) Always Below 1 Ω
      B2-6 (EO) - B3-5 (EI) Always Below 1 Ω
      B2-2 (BO) - Body ground Always 10 kΩ or higher
      B2-4 (SO) - Body ground Always 10 kΩ or higher
      B2-6 (EO) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. CHECK HARNESS AND CONNECTOR (FRONT CENTER SENSOR RH - FRONT CORNER SENSOR RH)


    1. Disconnect the B3 No. 1 ultrasonic sensor (front center sensor RH) connector.

    2. Disconnect the B4 No. 1 ultrasonic sensor (front corner sensor RH) connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      B3-2 (BO) - B4-1 (BI) Always Below 1 Ω
      B3-4 (SO) - B4-3 (SI) Always Below 1 Ω
      B3-6 (EO) - B4-5 (EI) Always Below 1 Ω
      B3-2 (BO) - Body ground Always 10 kΩ or higher
      B3-4 (SO) - Body ground Always 10 kΩ or higher
      B3-6 (EO) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. INSPECT NO. 1 ULTRASONIC SENSOR (FRONT CORNER SENSOR LH)


    1. A00JWTGE01

      Remove the No. 1 ultrasonic sensor (front corner sensor LH) Click here.

    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      1 (BI) - 5 (EI) Always 10 kΩ or higher
      1 (BI) - 2 (BO) Always 10 kΩ or higher
      3 (SI) - 4 (SO) Always Below 1 Ω
      5 (EI) - 6 (EO) Always Below 1 Ω

    NG

    REPLACE NO. 1 ULTRASONIC SENSOR (FRONT CORNER SENSOR LH) Click here

    OK

  7. INSPECT NO. 1 ULTRASONIC SENSOR (FRONT CENTER SENSOR LH)


    1. A00JWTGE01

      Remove the No. 1 ultrasonic sensor (front center sensor LH) Click here.

    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      1 (BI) - 5 (EI) Always 10 kΩ or higher
      1 (BI) - 2 (BO) Always 10 kΩ or higher
      3 (SI) - 4 (SO) Always Below 1 Ω
      5 (EI) - 6 (EO) Always Below 1 Ω

    NG

    REPLACE NO. 1 ULTRASONIC SENSOR (FRONT CENTER SENSOR LH) Click here

    OK

  8. INSPECT NO. 1 ULTRASONIC SENSOR (FRONT CENTER SENSOR RH)


    1. A00JWTGE01

      Remove the No. 1 ultrasonic sensor (front center sensor RH) Click here.

    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      1 (BI) - 5 (EI) Always 10 kΩ or higher
      1 (BI) - 2 (BO) Always 10 kΩ or higher
      3 (SI) - 4 (SO) Always Below 1 Ω
      5 (EI) - 6 (EO) Always Below 1 Ω

    NG

    REPLACE NO. 1 ULTRASONIC SENSOR (FRONT CENTER SENSOR RH) Click here

    OK

  9. REPLACE NO. 1 ULTRASONIC SENSOR (FRONT CORNER SENSOR RH)


    1. Replace the No. 1 ultrasonic sensor (front corner sensor RH) with a normally functioning sensor Click here.


    NEXT

  10. CHECK FOR DTC (C1AEC)


    1. Clear the DTCs Click here.

    2. Check for DTCs Click here.

      Result
      Result Proceed to
      DTC C1AEC is output A
      No DTC is output B

    B

    END (NO. 1 ULTRASONIC SENSOR [FRONT CORNER SENSOR RH] WAS DEFECTIVE)

    A

  11. REPLACE NO. 1 ULTRASONIC SENSOR (FRONT CENTER SENSOR LH)


    1. Replace the No. 1 ultrasonic sensor (front center sensor LH) with a normally functioning sensor Click here.

      Tech Tips

      All of the sensors are interchangeable. To confirm whether a sensor is functioning normally, switch it with a known good sensor from the other end of the vehicle.


    NEXT

  12. CHECK FOR DTC (C1AEC)


    1. Clear the DTCs Click here.

    2. Check for DTCs Click here.

      Result
      Result Proceed to
      DTC C1AEC is output A
      No DTC is output B

    B

    END (NO. 1 ULTRASONIC SENSOR [FRONT CENTER SENSOR LH] WAS DEFECTIVE)

    A

  13. REPLACE NO. 1 ULTRASONIC SENSOR (FRONT CENTER SENSOR RH)


    1. Replace the No. 1 ultrasonic sensor (front center sensor RH) with a normally functioning sensor Click here.

      Tech Tips

      All of the sensors are interchangeable. To confirm whether a sensor is functioning normally, switch it with a known good sensor from the other end of the vehicle.


    NEXT

  14. CHECK FOR DTC (C1AEC)


    1. Clear the DTCs Click here.

    2. Check for DTCs Click here.

      Result
      Result Proceed to
      DTC C1AEC is output A
      No DTC is output B

    B

    END (NO. 1 ULTRASONIC SENSOR [FRONT CENTER SENSOR RH] WAS DEFECTIVE)

    A

  15. REPLACE NO. 1 ULTRASONIC SENSOR (FRONT CORNER SENSOR RH)


    1. Replace the No. 1 ultrasonic sensor (front corner sensor RH) with a normally functioning sensor Click here.

      Tech Tips

      All of the sensors are interchangeable. To confirm whether a sensor is functioning normally, switch it with a known good sensor from the other end of the vehicle.


    NEXT

  16. CHECK FOR DTC (C1AEC)


    1. Clear the DTCs Click here.

    2. Check for DTCs Click here.

      Result
      Result Proceed to
      DTC C1AEC is output (for LHD) A
      DTC C1AEC is output (for RHD) B
      No DTC is output C

    B

    REPLACE CLEARANCE WARNING ECU Click here

    C

    END (NO. 1 ULTRASONIC SENSOR [FRONT CORNER SENSOR RH] WAS DEFECTIVE)

    A

    REPLACE CLEARANCE WARNING ECU Click here

  17. CHECK HARNESS AND CONNECTOR (PARKING ASSIST ECU - FRONT CORNER SENSOR LH)


    1. Disconnect the I2 parking assist ECU connector.

    2. Disconnect the B1 No. 1 ultrasonic sensor (front corner sensor LH) connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      I2-1 (CSB1) - B1-1 (BI) Always Below 1 Ω
      I2-2 (CSG1) - B1-5 (EI) Always Below 1 Ω
      I2-3 (LIN1) - B1-3 (SI) Always Below 1 Ω
      I2-1 (CSB1) - Body ground Always 10 kΩ or higher
      I2-2 (CSG1) - Body ground Always 10 kΩ or higher
      I2-3 (LIN1) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  18. CHECK HARNESS AND CONNECTOR (FRONT CORNER SENSOR LH - FRONT CENTER SENSOR LH)


    1. Disconnect the B1 No. 1 ultrasonic sensor (front corner sensor LH) connector.

    2. Disconnect the B2 No. 1 ultrasonic sensor (front center sensor LH) connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      B1-2 (BO) - B2-1 (BI) Always Below 1 Ω
      B1-4 (SO) - B2-3 (SI) Always Below 1 Ω
      B1-6 (EO) - B2-5 (EI) Always Below 1 Ω
      B1-2 (BO) - Body ground Always 10 kΩ or higher
      B1-4 (SO) - Body ground Always 10 kΩ or higher
      B1-6 (EO) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  19. CHECK HARNESS AND CONNECTOR (FRONT CENTER SENSOR LH - FRONT CENTER SENSOR RH)


    1. Disconnect the B2 No. 1 ultrasonic sensor (front center sensor LH) connector.

    2. Disconnect the B3 No. 1 ultrasonic sensor (front center sensor RH) connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      B2-2 (BO) - B3-1 (BI) Always Below 1 Ω
      B2-4 (SO) - B3-3 (SI) Always Below 1 Ω
      B2-6 (EO) - B3-5 (EI) Always Below 1 Ω
      B2-2 (BO) - Body ground Always 10 kΩ or higher
      B2-4 (SO) - Body ground Always 10 kΩ or higher
      B2-6 (EO) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  20. CHECK HARNESS AND CONNECTOR (FRONT CENTER SENSOR RH - FRONT CORNER SENSOR RH)


    1. Disconnect the B3 No. 1 ultrasonic sensor (front center sensor RH) connector.

    2. Disconnect the B4 No. 1 ultrasonic sensor (front corner sensor RH) connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      B3-2 (BO) - B4-1 (BI) Always Below 1 Ω
      B3-4 (SO) - B4-3 (SI) Always Below 1 Ω
      B3-6 (EO) - B4-5 (EI) Always Below 1 Ω
      B3-2 (BO) - Body ground Always 10 kΩ or higher
      B3-4 (SO) - Body ground Always 10 kΩ or higher
      B3-6 (EO) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  21. INSPECT NO. 1 ULTRASONIC SENSOR (FRONT CORNER SENSOR LH)


    1. A00JWTGE01

      Remove the No. 1 ultrasonic sensor (front corner sensor LH) Click here.

    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      1 (BI) - 5 (EI) Always 10 kΩ or higher
      1 (BI) - 2 (BO) Always 10 kΩ or higher
      3 (SI) - 4 (SO) Always Below 1 Ω
      5 (EI) - 6 (EO) Always Below 1 Ω

    NG

    REPLACE NO. 1 ULTRASONIC SENSOR (FRONT CORNER SENSOR LH) Click here

    OK

  22. INSPECT NO. 1 ULTRASONIC SENSOR (FRONT CENTER SENSOR LH)


    1. A00JWTGE01

      Remove the No. 1 ultrasonic sensor (front center sensor LH) Click here.

    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      1 (BI) - 5 (EI) Always 10 kΩ or higher
      1 (BI) - 2 (BO) Always 10 kΩ or higher
      3 (SI) - 4 (SO) Always Below 1 Ω
      5 (EI) - 6 (EO) Always Below 1 Ω

    NG

    REPLACE NO. 1 ULTRASONIC SENSOR (FRONT CENTER SENSOR LH) Click here

    OK

  23. INSPECT NO. 1 ULTRASONIC SENSOR (FRONT CENTER SENSOR RH)


    1. A00JWTGE01

      Remove the No. 1 ultrasonic sensor (front center sensor RH) Click here.

    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      1 (BI) - 5 (EI) Always 10 kΩ or higher
      1 (BI) - 2 (BO) Always 10 kΩ or higher
      3 (SI) - 4 (SO) Always Below 1 Ω
      5 (EI) - 6 (EO) Always Below 1 Ω

    NG

    REPLACE NO. 1 ULTRASONIC SENSOR (FRONT CENTER SENSOR RH) Click here

    OK

  24. REPLACE NO. 1 ULTRASONIC SENSOR (FRONT CORNER SENSOR RH)


    1. Replace the No. 1 ultrasonic sensor (front corner sensor RH) with a normally functioning sensor Click here.

      Tech Tips

      All of the sensors are interchangeable. To confirm whether a sensor is functioning normally, switch it with a known good sensor from the other end of the vehicle.


    NEXT

  25. CHECK FOR DTC (C1AEC)


    1. Clear the DTCs Click here.

    2. Check for DTCs Click here.

      Result
      Result Proceed to
      DTC C1AEC is output A
      No DTC is output B

    B

    END (NO. 1 ULTRASONIC SENSOR [FRONT CORNER SENSOR RH] WAS DEFECTIVE)

    A

  26. REPLACE NO. 1 ULTRASONIC SENSOR (FRONT CENTER SENSOR LH)


    1. Replace the No. 1 ultrasonic sensor (front center sensor LH) with a normally functioning sensor Click here.

      Tech Tips

      All of the sensors are interchangeable. To confirm whether a sensor is functioning normally, switch it with a known good sensor from the other end of the vehicle.


    NEXT

  27. CHECK FOR DTC (C1AEC)


    1. Clear the DTCs Click here.

    2. Check for DTCs Click here.

      Result
      Result Proceed to
      DTC C1AEC is output A
      No DTC is output B

    B

    END (NO. 1 ULTRASONIC SENSOR [FRONT CENTER SENSOR LH] WAS DEFECTIVE)

    A

  28. REPLACE NO. 1 ULTRASONIC SENSOR (FRONT CENTER SENSOR RH)


    1. Replace the No. 1 ultrasonic sensor (front center sensor RH) with a normally functioning sensor Click here.

      Tech Tips

      All of the sensors are interchangeable. To confirm whether a sensor is functioning normally, switch it with a known good sensor from the other end of the vehicle.


    NEXT

  29. CHECK FOR DTC (C1AEC)


    1. Clear the DTCs Click here.

    2. Check for DTCs Click here.

      Result
      Result Proceed to
      DTC C1AEC is output A
      No DTC is output B

    B

    END (NO. 1 ULTRASONIC SENSOR [FRONT CENTER SENSOR RH] WAS DEFECTIVE)

    A

  30. REPLACE NO. 1 ULTRASONIC SENSOR (FRONT CORNER SENSOR LH)


    1. Replace the No. 1 ultrasonic sensor (front corner sensor LH) with a normally functioning sensor Click here.

      Tech Tips

      All of the sensors are interchangeable. To confirm whether a sensor is functioning normally, switch it with a known good sensor from the other end of the vehicle.


    NEXT

  31. CHECK FOR DTC (C1AEC)


    1. Clear the DTCs Click here.

    2. Check for DTCs Click here.

      Result
      Result Proceed to
      DTC C1AEC is output (for LHD) A
      DTC C1AEC is output (for RHD) B
      No DTC is output C

    B

    REPLACE PARKING ASSIST ECU Click here

    C

    END (NO. 1 ULTRASONIC SENSOR [FRONT CORNER SENSOR LH] WAS DEFECTIVE)

    A

    REPLACE PARKING ASSIST ECU Click here