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DTC C1AEC: Front Sensor Communication Malfunction [08/2016 - 08/2019]: Procedure

  1. INITIALIZE NO. 1 ULTRASONIC SENSOR AND NO. 2 ULTRASONIC SENSOR 
    1. Initialize the No. 1 ultrasonic sensor (front right center and front left center sensor) and No. 2 ultrasonic sensor (front left sensor and front right sensor).

      Refer to CALIBRATION [08/2016 - 03/2018] , or refer to CALIBRATION [03/2018 - 08/2019]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  2

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

      Refer to DTC CHECK / CLEAR [08/2016 - ]

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

    2. Clear the DTCs.

      Refer to DTC CHECK / CLEAR [08/2016 - ]

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

    3. Recheck for DTCs.

      Refer to DTC CHECK / CLEAR [08/2016 - ]

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

      Result

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

    Result: 

    B 

    USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [08/2016 - 12/2017]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [12/2017 - 03/2018]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [03/2018 - 08/2019] 

    Result: 

    A 

    See step  3

  3. CHECK HARNESS AND CONNECTOR (CLEARANCE WARNING ECU ASSEMBLY - FRONT LEFT SENSOR) 
    1. Disconnect the J38 clearance warning ECU assembly connector.
    2. Disconnect the B1 No. 2 ultrasonic sensor connector.
    3. Measure the resistance according to the value (s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      J38-4 (BOF) - B1-4 (BI) Always Below 1 Ω
      J38-8 (SOF) - B1-5 (SI) Always Below 1 Ω
      J38-6 (E5) - B1-6 (EI) Always Below 1 Ω
      J38-4 (BOF) or B1-4 (BI) - Body ground Always 10 kΩ or higher
      J38-8 (SOF) or B1-5 (SI) - Body ground Always 10 kΩ or higher
      J38-6 (E5) or B1-6 (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 LEFT SENSOR - FRONT LEFT CENTER SENSOR) 
    1. Disconnect the B2*1 or B5*2 No. 1 ultrasonic sensor connector.
      1. *1: for Mesh Type Radiator Grille
      2. *2: for Bar Type Radiator Grille
    2. Measure the resistance according to the value (s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      B1-1 (BO) - B2-4 (BI)*1 Always Below 1 Ω
      B1-2 (SO) - B2-5 (SI)*1 Always Below 1 Ω
      B1-3 (EO) - B2-6 (EI)*1 Always Below 1 Ω
      B1-1 (BO) - B5-4 (BI)*2 Always Below 1 Ω
      B1-2 (SO) - B5-5 (SI)*2 Always Below 1 Ω
      B1-3 (EO) - B5-6 (EI)*2 Always Below 1 Ω
      B1-1 (BO) or B2-4 (BI) - Body ground*1 Always 10 kΩ or higher
      B1-2 (SO) or B2-5 (SI) - Body ground*1 Always 10 kΩ or higher
      B1-3 (EO) or B2-6 (EI) - Body ground*1 Always 10 kΩ or higher
      B1-1 (BO) or B5-4 (BI) - Body ground*2 Always 10 kΩ or higher
      B1-2 (SO) or B5-5 (SI) - Body ground*2 Always 10 kΩ or higher
      B1-3 (EO) or B5-6 (EI) - Body ground*2 Always 10 kΩ or higher
      1. *1: for Mesh Type Radiator Grille
      2. *2: for Bar Type Radiator Grille

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  5

  5. CHECK HARNESS AND CONNECTOR (FRONT LEFT CENTER SENSOR - FRONT RIGHT CENTER SENSOR) 
    1. Disconnect the B3*1 or B6*2 No. 1 ultrasonic sensor connector.
      1. *1: for Mesh Type Radiator Grille
      2. *2: for Bar Type Radiator Grille
    2. Measure the resistance according to the value (s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      B2-1 (BO) - B3-4 (BI)*1 Always Below 1 Ω
      B2-2 (SO) - B3-5 (SI)*1 Always Below 1 Ω
      B2-3 (EO) - B3-6 (EI)*1 Always Below 1 Ω
      B5-1 (BO) - B6-4 (BI)*2 Always Below 1 Ω
      B5-2 (SO) - B6-5 (SI)*2 Always Below 1 Ω
      B5-3 (EO) - B6-6 (EI)*2 Always Below 1 Ω
      B2-1 (BO) or B3-4 (BI) - Body ground*1 Always 10 kΩ or higher
      B2-2 (SO) or B3-5 (SI) - Body ground*1 Always 10 kΩ or higher
      B2-3 (EO) or B3-6 (EI) - Body ground*1 Always 10 kΩ or higher
      B5-1 (BO) or B6-4 (BI) - Body ground]*2 Always 10 kΩ or higher
      B5-2 (SO) or B6-5 (SI) - Body ground*2 Always 10 kΩ or higher
      B5-3 (EO) or B6-6 (EI) - Body ground*2 Always 10 kΩ or higher
      1. *1: for Mesh Type Radiator Grille
      2. *2: for Bar Type Radiator Grille

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  6

  6. CHECK HARNESS AND CONNECTOR (FRONT RIGHT CENTER SENSOR - FRONT RIGHT SENSOR) 
    1. Disconnect the B4 No. 2 ultrasonic sensor connector.
    2. Measure the resistance according to the value (s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      B3-1 (BO) - B4-4 (BI)*1 Always Below 1 Ω
      B3-2 (SO) - B4-5 (SI)*1 Always Below 1 Ω
      B3-3 (EO) - B4-6 (EI)*1 Always Below 1 Ω
      B6-1 (BO) - B4-4 (BI)*2 Always Below 1 Ω
      B6-2 (SO) - B4-5 (SI)*2 Always Below 1 Ω
      B6-3 (EO) - B4-6 (EI)*2 Always Below 1 Ω
      B3-1 (BO) or B4-4 (BI) - Body ground*1 Always 10 kΩ or higher
      B3-2 (SO) or B4-5 (SI) - Body ground*1 Always 10 kΩ or higher
      B3-3 (EO) or B4-6 (EI) - Body ground*1 Always 10 kΩ or higher
      B6-1 (BO) or B4-4 (BI) - Body ground*2 Always 10 kΩ or higher
      B6-2 (SO) or B4-5 (SI) - Body ground*2 Always 10 kΩ or higher
      B6-3 (EO) or B4-6 (EI) - Body ground*2 Always 10 kΩ or higher
      1. *1: for Mesh Type Radiator Grille
      2. *2: for Bar Type Radiator Grille

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  7

  7. INSPECT NO. 2 ULTRASONIC SENSOR (FRONT LEFT SENSOR) 
    1. Measure the resistance according to the value (s) in the table below.
      GTY565900Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component without harness connected
      (No. 2 Ultrasonic Sensor (Front Left Sensor))

      Standard Resistance

      Tester Connection Condition Specified Condition
      4 (BI) - 6 (EI) Always 10 kΩ or higher
      4 (BI) - 1 (BO) Always Below 1 Ω
      5 (SI) - 2 (SO) Always Below 30 Ω
      6 (EI) - 3 (EO) Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE NO. 2 ULTRASONIC SENSOR (FRONT LEFT SENSOR). Refer to  REMOVAL [08/2016 - 08/2019] 

    Result: 

    OK 

    See step  8

  8. INSPECT NO. 1 ULTRASONIC SENSOR (FRONT LEFT CENTER SENSOR) 
    1. Measure the resistance according to the value (s) in the table below.
      GTY565900Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component without harness connected
      (No. 1 Ultrasonic Sensor (Front Left Center Sensor))

      Standard Resistance

      Tester Connection Condition Specified Condition
      4 (BI) - 6 (EI) Always 10 kΩ or higher
      4 (BI) - 1 (BO) Always Below 1 Ω
      5 (SI) - 2 (SO) Always Below 30 Ω
      6 (EI) - 3 (EO) Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE NO. 1 ULTRASONIC SENSOR (FRONT LEFT CENTER SENSOR). Refer to  REMOVAL [08/2016 - 08/2019] 

    Result: 

    OK 

    See step  9

  9. INSPECT NO. 1 ULTRASONIC SENSOR (FRONT RIGHT CENTER SENSOR) 
    1. Measure the resistance according to the value (s) in the table below.
      GTY565900Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component without harness connected
      (No. 1 Ultrasonic Sensor (Front Right Center Sensor))

      Standard Resistance

      Tester Connection Condition Specified Condition
      4 (BI) - 6 (EI) Always 10 kΩ or higher
      4 (BI) - 1 (BO) Always Below 1 Ω
      5 (SI) - 2 (SO) Always Below 30 Ω
      6 (EI) - 3 (EO) Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE NO. 1 ULTRASONIC SENSOR (FRONT RIGHT CENTER SENSOR). Refer to  REMOVAL [08/2016 - 08/2019] 

    Result: 

    OK 

    See step  10

  10. INSPECT NO. 2 ULTRASONIC SENSOR (FRONT RIGHT SENSOR) 
    1. Measure the resistance according to the value (s) in the table below.
      GTY565900Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component without harness connected
      (No. 2 Ultrasonic Sensor (Front Right Sensor))

      Standard Resistance

      Tester Connection Condition Specified Condition
      4 (BI) - 6 (EI) Always 10 kΩ or higher
      4 (BI) - 1 (BO) Always Below 1 Ω
      5 (SI) - 2 (SO) Always Below 30 Ω
      6 (EI) - 3 (EO) Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE NO. 2 ULTRASONIC SENSOR (FRONT RIGHT SENSOR). Refer to  REMOVAL [08/2016 - 08/2019] 

    Result: 

    OK 

    See step  11

  11. REPLACE NO. 2 ULTRASONIC SENSOR (FRONT LEFT SENSOR) 

    See step  2

    Result

    Proceed to
    NEXT

    Result: 

    NEXT 

    See step  12

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

      Refer to DTC CHECK / CLEAR [08/2016 - ]

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

    2. Check for DTCs.

      Refer to DTC CHECK / CLEAR [08/2016 - ]

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

      Result

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

    Result: 

    B 

    END (FRONT LEFT SENSOR WAS DEFECTIVE) 

    Result: 

    A 

    See step  13

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

    See step  2

    Result

    Proceed to
    NEXT

    Result: 

    NEXT 

    See step  14

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

      Refer to DTC CHECK / CLEAR [08/2016 - ]

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

    2. Check for DTCs.

      Refer to DTC CHECK / CLEAR [08/2016 - ]

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

      Result

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

    Result: 

    B 

    END (FRONT LEFT CENTER SENSOR WAS DEFECTIVE) 

    Result: 

    A 

    See step  15

  15. REPLACE NO. 1 ULTRASONIC SENSOR (FRONT RIGHT CENTER SENSOR) 

    See step  2

    Result

    Proceed to
    NEXT

    Result: 

    NEXT 

    See step  16

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

      Refer to DTC CHECK / CLEAR [08/2016 - ]

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

    2. Check for DTCs.

      Refer to DTC CHECK / CLEAR [08/2016 - ]

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

      Result

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

    Result: 

    B 

    END (FRONT RIGHT CENTER SENSOR WAS DEFECTIVE) 

    Result: 

    A 

    See step  17

  17. REPLACE NO. 2 ULTRASONIC SENSOR (FRONT RIGHT SENSOR) 

    See step  2

    Result

    Proceed to
    NEXT

    Result: 

    NEXT 

    See step  18

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

      Refer to DTC CHECK / CLEAR [08/2016 - ]

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

    2. Check for DTCs.

      Refer to DTC CHECK / CLEAR [08/2016 - ]

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

      Result

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

    Result: 

    A 

    REPLACE CLEARANCE WARNING ECU ASSEMBLY. Refer to  REMOVAL [08/2016 - 03/2018]  , or refer to  REMOVAL [03/2018 - 08/2019] 

    Result: 

    B 

    END (FRONT RIGHT SENSOR WAS DEFECTIVE) 

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