LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Lexus >> 2017 >> NX 200t Base, AWD >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Drivers Assistance Systems - ADAS >> Intuitive Parking Assist System (W/O Intelligent Clearance Sonar System) - Diagnostic Codes & Symptom Tests >> INTUITIVE PARKING ASSIST SYSTEM (w/o Intelligent Clearance Sonar System) >> DTC C1AEC: Front Sensor Communication Malfunction [09/2017 - 07/2020] >> Procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

DTC C1AEC: Front Sensor Communication Malfunction [09/2017 - 07/2020]: Procedure

  1. INITIALIZE FRONT CORNER ULTRASONIC SENSOR AND FRONT CENTER ULTRASONIC SENSOR 
    1. Initialize the front corner ultrasonic sensor (FL and FR sensor) and front center ultrasonic sensor (FLC and FRC sensor).

      Refer to CALIBRATION [09/2017 - 07/2020]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  2

  2. CHECK DTC OUTPUT (C1AEC) 
    1. Check for DTCs.

      Refer to DTC CHECK / CLEAR [09/2017 - 07/2020]

      Body Electrical > Advanced Parking Guidance/ICS/Intuitive P/A > Trouble Codes 

    2. Clear the DTCs.

      Refer to DTC CHECK / CLEAR [09/2017 - 07/2020]

      Body Electrical > Advanced Parking Guidance/ICS/Intuitive P/A > Clear DTCs 

    3. Recheck for DTCs.

      Refer to DTC CHECK / CLEAR [09/2017 - 07/2020]

      Body Electrical > Advanced Parking Guidance/ICS/Intuitive P/A > Trouble Codes 

      Result

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

    Result: 

    A 

    USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [09/2017 - 05/2019]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [05/2019 - 10/2019]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [10/2019 - 07/2020] 

    Result: 

    B 

    See step  3

  3. CHECK HARNESS AND CONNECTOR (CLEARANCE WARNING ECU ASSEMBLY - FRONT CORNER ULTRASONIC SENSOR [FR SENSOR]) 
    1. Disconnect the I20 clearance warning ECU assembly connector.
    2. Disconnect the B6 front corner ultrasonic sensor (FR sensor) connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      I20-4 (BOF) - B6-4 (BI) Always Below 1 Ω
      I20-8 (SOF) - B6-5 (SI) Always Below 1 Ω
      I20-6 (E5) - B6-6 (EI) Always Below 1 Ω
      I20-4 (BOF) or B6-4 (BI) - Body ground Always 10 kΩ or higher
      I20-8 (SOF) or B6-5 (SI) - Body ground Always 10 kΩ or higher
      I20-6 (E5) or B6-6 (EI) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  4

  4. CHECK HARNESS AND CONNECTOR (FRONT CORNER ULTRASONIC SENSOR [FR SENSOR] - FRONT CENTER ULTRASONIC SENSOR [FRC SENSOR]) 
    1. Disconnect the B6 front corner ultrasonic sensor (FR sensor) connector.
    2. Disconnect the B7 front center ultrasonic sensor (FRC sensor) connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      B6-1 (BO) - B7-4 (BI) Always Below 1 Ω
      B6-2 (SO) - B7-5 (SI) Always Below 1 Ω
      B6-3 (EO) - B7-6 (EI) Always Below 1 Ω
      B6-1 (BO) or B7-4 (BI) - Body ground Always 10 kΩ or higher
      B6-2 (SO) or B7-5 (SI) - Body ground Always 10 kΩ or higher
      B6-3 (EO) or B7-6 (EI) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  5

  5. CHECK HARNESS AND CONNECTOR (FRONT CENTER ULTRASONIC SENSOR [FRC SENSOR] - FRONT CENTER ULTRASONIC SENSOR [FLC SENSOR]) 
    1. Disconnect the B7 front center ultrasonic sensor (FRC sensor) connector.
    2. Disconnect the B8 front center ultrasonic sensor (FLC sensor) connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      B7-1 (BO) - B8-4 (BI) Always Below 1 Ω
      B7-2 (SO) - B8-5 (SI) Always Below 1 Ω
      B7-3 (EO) - B8-6 (EI) Always Below 1 Ω
      B7-1 (BO) or B8-4 (BI) - Body ground Always 10 kΩ or higher
      B7-2 (SO) or B8-5 (SI) - Body ground Always 10 kΩ or higher
      B7-3 (EO) or B8-6 (EI) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  6

  6. CHECK HARNESS AND CONNECTOR (FRONT CENTER ULTRASONIC SENSOR [FLC SENSOR] - FRONT CORNER ULTRASONIC SENSOR [FL SENSOR]) 
    1. Disconnect the B8 front center ultrasonic sensor (FLC sensor) connector.
    2. Disconnect the B9 front corner ultrasonic sensor (FL sensor) connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      B8-1 (BO) - B9-4 (BI) Always Below 1 Ω
      B8-2 (SO) - B9-5 (SI) Always Below 1 Ω
      B8-3 (EO) - B9-6 (EI) Always Below 1 Ω
      B8-1 (BO) or B9-4 (BI) - Body ground Always 10 kΩ or higher
      B8-2 (SO) or B9-5 (SI) - Body ground Always 10 kΩ or higher
      B8-3 (EO) or B9-6 (EI) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  7

  7. INSPECT FRONT CORNER ULTRASONIC SENSOR (FL SENSOR) 
    1. Remove the front corner ultrasonic sensor (FL sensor).

      Refer to REMOVAL [09/2017 - 07/2020]

    2. Inspect the front corner ultrasonic sensor (FL sensor).

      Refer to INSPECTION [09/2017 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE FRONT CORNER ULTRASONIC SENSOR (FL SENSOR). Refer to  REMOVAL [09/2017 - 07/2020] 

    Result: 

    OK 

    See step  8

  8. INSPECT FRONT CENTER ULTRASONIC SENSOR (FLC SENSOR) 
    1. Remove the front center ultrasonic sensor (FLC sensor).

      Refer to REMOVAL [09/2017 - 07/2020]

    2. Inspect the front center ultrasonic sensor (FLC sensor).

      Refer to INSPECTION [09/2017 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE FRONT CENTER ULTRASONIC SENSOR (FLC SENSOR). Refer to  REMOVAL [09/2017 - 07/2020] 

    Result: 

    OK 

    See step  9

  9. INSPECT FRONT CENTER ULTRASONIC SENSOR (FRC SENSOR) 
    1. Remove the front center ultrasonic sensor (FRC sensor).

      Refer to REMOVAL [09/2017 - 07/2020]

    2. Inspect the front center ultrasonic sensor (FRC sensor).

      Refer to INSPECTION [09/2017 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE FRONT CENTER ULTRASONIC SENSOR (FRC SENSOR). Refer to  REMOVAL [09/2017 - 07/2020] 

    Result: 

    OK 

    See step  10

  10. INSPECT FRONT CORNER ULTRASONIC SENSOR (FR SENSOR) 
    1. Remove the front corner ultrasonic sensor (FR sensor).

      Refer to REMOVAL [09/2017 - 07/2020]

    2. Inspect the front corner ultrasonic sensor (FR sensor).

      Refer to INSPECTION [09/2017 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE FRONT CORNER ULTRASONIC SENSOR (FR SENSOR). Refer to  REMOVAL [09/2017 - 07/2020] 

    Result: 

    OK 

    See step  11

  11. REPLACE FRONT CORNER ULTRASONIC SENSOR (FL SENSOR) 
    1. Replace the front corner ultrasonic sensor (FL sensor) with a known good one.

      Refer to REMOVAL [09/2017 - 07/2020]

      HINT: 

      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.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  12

  12. CHECK DTC OUTPUT (C1AEC) 
    1. Clear the DTCs.

      Refer to DTC CHECK / CLEAR [09/2017 - 07/2020]

      Body Electrical > Advanced Parking Guidance/ICS/Intuitive P/A > Clear DTCs 

    2. Check for DTCs.

      Refer to DTC CHECK / CLEAR [09/2017 - 07/2020]

      Body Electrical > Advanced Parking Guidance/ICS/Intuitive P/A > Trouble Codes 

      Result

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

    Result: 

    A 

    END (FRONT CORNER ULTRASONIC SENSOR [FL SENSOR] WAS DEFECTIVE) 

    Result: 

    B 

    See step  13

  13. REPLACE FRONT CENTER ULTRASONIC SENSOR (FLC SENSOR) 
    1. Replace the front center ultrasonic sensor (FLC sensor) with a known good one.

      Refer to REMOVAL [09/2017 - 07/2020]

      HINT: 

      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.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  14

  14. CHECK DTC OUTPUT (C1AEC) 
    1. Clear the DTCs.

      Refer to DTC CHECK / CLEAR [09/2017 - 07/2020]

      Body Electrical > Advanced Parking Guidance/ICS/Intuitive P/A > Clear DTCs 

    2. Check for DTCs.

      Refer to DTC CHECK / CLEAR [09/2017 - 07/2020]

      Body Electrical > Advanced Parking Guidance/ICS/Intuitive P/A > Trouble Codes 

      Result

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

    Result: 

    A 

    END (FRONT CENTER ULTRASONIC SENSOR [FLC SENSOR] WAS DEFECTIVE) 

    Result: 

    B 

    See step  15

  15. REPLACE FRONT CENTER ULTRASONIC SENSOR (FRC SENSOR) 
    1. Replace the front center ultrasonic sensor (FRC sensor) with a known good one.

      Refer to REMOVAL [09/2017 - 07/2020]

      HINT: 

      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.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  16

  16. CHECK DTC OUTPUT (C1AEC) 
    1. Clear the DTCs.

      Refer to DTC CHECK / CLEAR [09/2017 - 07/2020]

      Body Electrical > Advanced Parking Guidance/ICS/Intuitive P/A > Clear DTCs 

    2. Check for DTCs.

      Refer to DTC CHECK / CLEAR [09/2017 - 07/2020]

      Body Electrical > Advanced Parking Guidance/ICS/Intuitive P/A > Trouble Codes 

      Result

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

    Result: 

    A 

    END (FRONT CENTER ULTRASONIC SENSOR [FRC SENSOR] WAS DEFECTIVE) 

    Result: 

    B 

    See step  17

  17. REPLACE FRONT CORNER ULTRASONIC SENSOR (FR SENSOR) 
    1. Replace the front corner ultrasonic sensor (FR sensor) with a known good one.

      Refer to REMOVAL [09/2017 - 07/2020]

      HINT: 

      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.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  18

  18. CHECK DTC OUTPUT (C1AEC) 
    1. Clear the DTCs.

      Refer to DTC CHECK / CLEAR [09/2017 - 07/2020]

      Body Electrical > Advanced Parking Guidance/ICS/Intuitive P/A > Clear DTCs 

    2. Check for DTCs.

      Refer to DTC CHECK / CLEAR [09/2017 - 07/2020]

      Body Electrical > Advanced Parking Guidance/ICS/Intuitive P/A > Trouble Codes 

      Result

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

    Result: 

    A 

    END (FRONT CORNER ULTRASONIC SENSOR [FR SENSOR] WAS DEFECTIVE) 

    Result: 

    B 

    REPLACE CLEARANCE WARNING ECU ASSEMBLY. Refer to  REMOVAL [10/2014 - 05/2019]  , or refer to  REMOVAL [05/2019 - ] 

scientia non olet · About LEMON Manuals