LEXUS PARKING ASSIST-SENSOR SYSTEM (w/ Side Monitor 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

  • Parking assist ECU

WIRING DIAGRAM

A019L05E11

INSPECTION PROCEDURE

Note


  • If DTCs are output after repairs, turn the engine switch on (IG) and turn the LEXUS parking assist-sensor system on. Then clear the DTCs Click here.

  • Depending on the parts that are replaced or operations that are performed during vehicle inspection or maintenance, calibration of other systems may be needed Click here.

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
    A
  2. CHECK HARNESS AND CONNECTOR (PARKING ASSIST ECU - FRONT LEFT SENSOR)


    1. Disconnect the F104 parking assist ECU connector.

    2. Disconnect the e1 No. 1 ultrasonic sensor connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      F104-5 (CSB1) - e1-1 (BI) Always Below 1 Ω
      F104-23 (LIN1) - e1-3 (SI) Always Below 1 Ω
      F104-6 (CSG1) - e1-5 (EI) Always Below 1 Ω
      F104-5 (CSB1) - Body ground Always 10 kΩ or higher
      F104-23 (LIN1) - Body ground Always 10 kΩ or higher
      F104-6 (CSG1) - Body ground Always 10 kΩ or higher

    NG
    OK
  3. CHECK HARNESS AND CONNECTOR (FRONT LEFT SENSOR - FRONT LEFT CENTER SENSOR)


    1. Disconnect the e2 No. 1 ultrasonic sensor connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      e1-2 (BO) - e2-1 (BI) Always Below 1 Ω
      e1-4 (SO) - e2-3 (SI) Always Below 1 Ω
      e1-6 (EO) - e2-5 (EI) Always Below 1 Ω
      e1-2 (BO) - Body ground Always 10 kΩ or higher
      e1-4 (SO) - Body ground Always 10 kΩ or higher
      e1-6 (EO) - Body ground Always 10 kΩ or higher

    NG
    OK
  4. CHECK HARNESS AND CONNECTOR (FRONT LEFT CENTER SENSOR - FRONT RIGHT CENTER SENSOR)


    1. Disconnect the e3 No. 1 ultrasonic sensor connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      e2-2 (BO) - e3-1 (BI) Always Below 1 Ω
      e2-4 (SO) - e3-3 (SI) Always Below 1 Ω
      e2-6 (EO) - e3-5 (EI) Always Below 1 Ω
      e2-2 (BO) - Body ground Always 10 kΩ or higher
      e2-4 (SO) - Body ground Always 10 kΩ or higher
      e2-6 (EO) - Body ground Always 10 kΩ or higher

    NG
    OK
  5. CHECK HARNESS AND CONNECTOR (FRONT RIGHT CENTER SENSOR - FRONT RIGHT SENSOR)


    1. Disconnect the e4 No. 1 ultrasonic sensor connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      e3-2 (BO) - e4-1 (BI) Always Below 1 Ω
      e3-4 (SO) - e4-3 (SI) Always Below 1 Ω
      e3-6 (EO) - e4-5 (EI) Always Below 1 Ω
      e3-2 (BO) - Body ground Always 10 kΩ or higher
      e3-4 (SO) - Body ground Always 10 kΩ or higher
      e3-6 (EO) - Body ground Always 10 kΩ or higher

    NG
    OK
  6. INSPECT NO. 1 ULTRASONIC SENSOR (FRONT LEFT SENSOR)


    1. A019LMTE01
      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
    OK
  7. INSPECT NO. 1 ULTRASONIC SENSOR (FRONT LEFT CENTER SENSOR)


    1. A019LMTE01
      Text in Illustration
      *a

      Component without harness connected

      (No. 1 Ultrasonic Sensor (Front Left Center 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
    OK
  8. INSPECT NO. 1 ULTRASONIC SENSOR (FRONT RIGHT CENTER SENSOR)


    1. A019LMTE01
      Text in Illustration
      *a

      Component without harness connected

      (No. 1 Ultrasonic Sensor (Front Right Center 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
    OK
  9. 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
  10. 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
    A
  11. REPLACE NO. 1 ULTRASONIC SENSOR (FRONT RIGHT CENTER SENSOR)


    1. Replace the No. 1 ultrasonic sensor (front right center 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
  12. 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
    A
  13. REPLACE NO. 1 ULTRASONIC SENSOR (FRONT LEFT CENTER SENSOR)


    1. Replace the No. 1 ultrasonic sensor (front left center 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
  14. 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
    A
  15. 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
  16. 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
    A