TOYOTA PARKING ASSIST-SENSOR SYSTEM, Diagnostic DTC:C1AEC

DTC Code DTC Name
C1AEC Front Sensor Communication Malfunction

DESCRIPTION

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

DTC No. 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 engine switch is turned on (IG).

  • Front ultrasonic sensor circuit

  • Clearance warning ECU assembly

WIRING DIAGRAM

A01CE1OE02

INSPECTION PROCEDURE

PROCEDURE


  1. CHECK DTC OUTPUT (C1AEC)


    1. Check for DTCs Click here.

    2. Clear the DTCs Click here.

    3. Recheck for DTCs Click here.

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

    B

    USE SIMULATION METHOD TO CHECK Click here

    A

  2. CHECK HARNESS AND CONNECTOR (CLEARANCE WARNING ECU ASSEMBLY - FRONT LEFT SENSOR)


    1. Disconnect the F2 connector from the clearance warning ECU assembly.

    2. Disconnect the C4 connector from the No. 1 ultrasonic sensor.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      F2-9 (BOF) - C4-1 (BI) Always Below 1 Ω
      F2-8 (SOF) - C4-3 (SI) Always Below 1 Ω
      F2-24 (E1) - C4-5 (EI) Always Below 1 Ω
      F2-9 (BOF) - Body ground Always 10 kΩ or higher
      F2-8 (SOF) - Body ground Always 10 kΩ or higher
      F2-24 (E1) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. CHECK HARNESS AND CONNECTOR (FRONT LEFT SENSOR - FRONT RIGHT SENSOR)


    1. Disconnect the C3 connector from the No. 1 ultrasonic sensor.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      C4-2 (BO) - C3-1 (BI) Always Below 1 Ω
      C4-4 (SO) - C3-3 (SI) Always Below 1 Ω
      C4-6 (EO) - C3-5 (EI) Always Below 1 Ω
      C4-2 (BO) - Body ground Always 10 kΩ or higher
      C4-4 (SO) - Body ground Always 10 kΩ or higher
      C4-6 (EO) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. INSPECT NO. 1 ULTRASONIC SENSOR (FRONT LEFT SENSOR)


    1. A01CDA8E01
      Text in Illustration
      *a

      Component without harness connected

      (No. 1 Ultrasonic Sensor (Front Left Sensor))

      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 LEFT SENSOR) Click here

    OK

  5. REPLACE NO. 1 ULTRASONIC SENSOR (FRONT LEFT SENSOR)


    1. Replace the No. 1 ultrasonic sensor (front left sensor) with a known good one 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

  6. CHECK DTC OUTPUT (C1AEC)


    1. Clear the DTCs Click here.

    2. Check for DTCs Click here.

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

    B

    END (FRONT LEFT SENSOR WAS DEFECTIVE)

    A

  7. REPLACE NO. 1 ULTRASONIC SENSOR (FRONT RIGHT SENSOR)


    1. Replace the No. 1 ultrasonic sensor (front right sensor) with a known good one 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

  8. CHECK DTC OUTPUT (C1AEC)


    1. Clear the DTCs Click here.

    2. Check for DTCs Click here.

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

    B

    END (FRONT RIGHT SENSOR WAS DEFECTIVE)

    A

    REPLACE CLEARANCE WARNING ECU ASSEMBLY Click here