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Home >> Lexus >> 2020 >> UX 200 Luxury >> Repair and Diagnosis >> External Pages >> Different car >> Section 65 (Electronically Controlled Brake System (Diagnostic Codes) (2 Of 4) (Hybrid)) >> ELECTRONICALLY CONTROLLED BRAKE SYSTEM (for HV Model) >> DTC C1403: Malfunction in Rear Speed Sensor RH Circuit; DTC C1404: Malfunction in Rear Speed Sensor LH Circuit [10/2018 - ] >> Procedure

DTC C1403: Malfunction in Rear Speed Sensor RH Circuit; DTC C1404: Malfunction in Rear Speed Sensor LH Circuit [10/2018 - ]: Procedure

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  1. CHECK DTC 
    1. Clear the DTCs.

      Refer to DTC CHECK / CLEAR [10/2018 - ]

      Chassis > ABS/VSC/TRAC > Clear DTCs 

    2. Turn the power switch off.
    3. Turn the power switch on (IG).
    4. Check if the same DTC is output.

      Refer to DTC CHECK / CLEAR [10/2018 - ]

      Chassis > ABS/VSC/TRAC > Trouble Codes 

      Result

      Result Proceed to
      DTC C1403 is output. A
      DTC C1404 is output. B

    Result: 

    B 

    See step  8

    Result: 

    A 

    See step  2

  2. CHECK REAR SPEED SENSOR RH INSTALLATION 
    1. Check the rear speed sensor RH installation.

      OK

      There is no clearance between the sensor and the rear axle hub.

      GTY806229Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *A for 2WD
      *B for AWD
      *a OK
      *b NG

      Result

      Result Proceed to
      OK (for 2WD) A
      OK (for AWD) B
      NG (for 2WD) C
      NG (for AWD) D

    Result: 

    A 

    See step  4

    Result: 

    C 

    REPLACE REAR AXLE HUB AND BEARING ASSEMBLY RH. Refer to  REMOVAL [10/2018 - 07/2022]  , or refer to  REMOVAL [07/2022 - ] 

    Result: 

    D 

    REINSTALL OR REPLACE REAR SPEED SENSOR RH. Refer to  REMOVAL [10/2018 - ] 

    Result: 

    B 

    See step  3

  3. CHECK REAR SPEED SENSOR RH (CHECK FOR FOREIGN MATTER) 
    1. Remove the rear speed sensor RH.

      Refer to REMOVAL [10/2018 - ]

    2. Check the speed sensor tip.

      OK

      The sensor tip is free of scratches, oil, and foreign matter.

      NOTE:
      • If there is oil or foreign matter on the speed sensor, clean the speed sensor.
      • If the speed sensor is damaged, replace the speed sensor with a new one.
      • Check the speed sensor signal after cleaning or replacement.

        Refer to TEST MODE PROCEDURE [10/2018 - ]

      Result

      Proceed to 
      OK
      NG

    Result: 

    NG 

    CLEAN OR REPLACE REAR SPEED SENSOR RH 

    Result: 

    OK 

    See step  4

  4. READ VALUE USING TECHSTREAM (RR WHEEL SPEED) 
    1. Select the Data List on the Techstream.

      Refer to DATA LIST / ACTIVE TEST [10/2018 - ]

      Chassis > ABS/VSC/TRAC > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      RR Wheel Speed Rear speed sensor RH Min.: 0 km/h (0 mph), Max.: 326.4 km/h (203 mph) Vehicle stopped: 0 km/h (0 mph) When driving at constant speed: No large fluctuations

      Chassis > ABS/VSC/TRAC > Data List 

      Tester Display
      RR Wheel Speed
    2. Check the rear speed sensor RH output value.

      OK

      The output value changes in accordance with the vehicle speed.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [10/2018 - ] 

    Result: 

    NG 

    See step  5

  5. INSPECT NO. 1 PARKING BRAKE WIRE ASSEMBLY 
    1. Turn the power switch off.
      GTY776440Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of skid control sensor wire RH (No. 1 parking brake wire assembly)
      *b Front view of wire harness connector
      (to Sensor Side Connector)
      *c Front view of wire harness connector
      (to Vehicle Side Connector)
    2. Make sure that there is no looseness at the locking part and the connecting part of the connectors.

      OK

      The connector is securely connected.

    3. Disconnect the j1 and jN1 skid control sensor wire RH (No. 1 parking brake wire assembly) connectors.
    4. Check both the connector case and the terminals for deformation and corrosion.

      OK

      No deformation or corrosion.

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

      Standard Resistance

      Tester Connection Condition Specified Condition
      j1-2 (+) - jN1-1 (RR+) Always Below 1 Ω
      j1-2 (+) or jN1-1 (RR+) - Body ground and other terminals Always 10 kΩ or higher
      j1-1 (-) - jN1-2 (RR-) Always Below 1 Ω
      j1-1 (-) or jN1-2 (RR-) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE NO. 1 PARKING BRAKE WIRE ASSEMBLY 

    Result: 

    OK 

    See step  6

  6. CHECK HARNESS AND CONNECTOR (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY - NO. 1 PARKING BRAKE WIRE ASSEMBLY) 
    1. Make sure that there is no looseness at the locking part and the connecting part of the connector.

      OK

      The connector is securely connected.

    2. Disconnect the A37 skid control ECU (brake booster with master cylinder assembly) connector.
    3. Check both the connector case and the terminals for deformation and corrosion.

      OK

      No deformation or corrosion.

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

      Standard Resistance

      Tester Connection Condition Specified Condition
      A37-7 (RR+) - jN1-1 (RR+) Always Below 1 Ω
      A37-7 (RR+) or jN1-1 (RR+) - Body ground Always 10 kΩ or higher
      A37-8 (RR-) - jN1-2 (RR-) Always Below 1 Ω
      A37-8 (RR-) or jN1-2 (RR-) - Body ground Always 10 kΩ or higher
      NOTE:

      Check the rear speed sensor RH signal after replacement.

      Refer to TEST MODE PROCEDURE [10/2018 - ]

      HINT: 

      The rear speed sensor RH and rear speed sensor rotor RH are incorporated into the rear axle hub and bearing assembly RH. (for 2WD)

      If the rear speed sensor RH and rear speed sensor rotor RH need to be replaced, replace the rear axle hub and bearing assembly RH. (for 2WD)

      Result

      Result Proceed to
      OK (for 2WD) A
      OK (for AWD) B
      NG C

    Result: 

    A 

    REPLACE REAR AXLE HUB AND BEARING ASSEMBLY RH. Refer to  REMOVAL [10/2018 - 07/2022]  , or refer to  REMOVAL [07/2022 - ] 

    Result: 

    C 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    B 

    See step  7

  7. CHECK REAR SPEED SENSOR ROTOR (REAR AXLE HUB AND BEARING ASSEMBLY RH) (CHECK FOR FOREIGN MATTER) 
    1. Remove the rear speed sensor rotor (rear axle hub and bearing assembly RH).

      Refer to REMOVAL [10/2018 - 07/2022] , or refer to REMOVAL [07/2022 - ]

    2. Check the speed sensor rotor.

      OK

      The rotor is free of scratches, oil, and foreign matter.

      NOTE:
      • If there is oil or foreign matter on the speed sensor rotor, clean the speed sensor rotor.
      • If the speed sensor rotor is damaged, replace the speed sensor rotor with a new one.
      • Check the speed sensor signal after cleaning or replacement.

        Refer to TEST MODE PROCEDURE [10/2018 - ]

      HINT: 

      • The rear speed sensor rotor is incorporated into the rear axle hub and bearing assembly RH.
      • If the rear speed sensor rotor needs to be replaced, replace it together with the rear axle hub and bearing assembly RH.

      Result

      Result  Proceed to
      OK  A
      NG (The speed sensor rotor is damaged.)  B
      NG (There is foreign matter on the speed sensor rotor.)  C

    Result: 

    A 

    REPLACE REAR SPEED SENSOR RH. Refer to  REMOVAL [10/2018 - ] 

    Result: 

    B 

    REPLACE REAR AXLE HUB AND BEARING ASSEMBLY RH. Refer to  REMOVAL [10/2018 - 07/2022]  , or refer to  REMOVAL [07/2022 - ] 

    Result: 

    C 

    CLEAN REAR SPEED SENSOR ROTOR (REAR AXLE HUB AND BEARING ASSEMBLY RH) 

  8. CHECK REAR SPEED SENSOR LH INSTALLATION 
    1. Check the rear speed sensor LH installation.

      OK

      There is no clearance between the sensor and the rear axle hub.

      GTY806229Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *A for 2WD
      *B for AWD
      *a OK
      *b NG

      Result

      Result Proceed to
      OK (for 2WD) A
      OK (for AWD) B
      NG (for 2WD) C
      NG (for AWD) D

    Result: 

    A 

    See step  10

    Result: 

    C 

    REPLACE REAR AXLE HUB AND BEARING ASSEMBLY LH. Refer to  REMOVAL [10/2018 - 07/2022]  , or refer to  REMOVAL [07/2022 - ] 

    Result: 

    D 

    REINSTALL OR REPLACE REAR SPEED SENSOR LH. Refer to  REMOVAL [10/2018 - ] 

    Result: 

    B 

    See step  9

  9. CHECK REAR SPEED SENSOR LH (CHECK FOR FOREIGN MATTER) 
    1. Remove the rear speed sensor LH.

      Refer to REMOVAL [10/2018 - ]

    2. Check the speed sensor tip.

      OK

      The sensor tip is free of scratches, oil, and foreign matter.

      NOTE:
      • If there is oil or foreign matter on the speed sensor, clean the speed sensor.
      • If the speed sensor is damaged, replace the speed sensor with a new one.
      • Check the speed sensor signal after cleaning or replacement.

        Refer to TEST MODE PROCEDURE [10/2018 - ]

      Result

      Proceed to 
      OK
      NG

    Result: 

    NG 

    CLEAN OR REPLACE REAR SPEED SENSOR RH 

    Result: 

    OK 

    See step  10

  10. READ VALUE USING TECHSTREAM (RL WHEEL SPEED) 
    1. Select the Data List on the Techstream.

      Refer to DATA LIST / ACTIVE TEST [10/2018 - ]

      Chassis > ABS/VSC/TRAC > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      RL Wheel Speed Rear speed sensor LH Min.: 0 km/h (0 mph), Max.: 326.4 km/h (203 mph) Vehicle stopped: 0 km/h (0 mph) When driving at constant speed: No large fluctuations

      Chassis > ABS/VSC/TRAC > Data List 

      Tester Display
      RL Wheel Speed
    2. Check the rear speed sensor LH output value.

      OK

      The output value changes in accordance with the vehicle speed.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [10/2018 - ] 

    Result: 

    NG 

    See step  11

  11. INSPECT NO. 2 PARKING BRAKE WIRE ASSEMBLY 
    1. Turn the power switch off.
      GTY776441Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of skid control sensor wire LH (No. 2 parking brake wire assembly)
      *b Front view of wire harness connector
      (to Sensor Side Connector)
      *c Front view of wire harness connector
      (to Vehicle Side Connector)
    2. Make sure that there is no looseness at the locking part and the connecting part of the connectors.

      OK

      The connector is securely connected.

    3. Disconnect the k1 and kN1 skid control sensor wire LH (No. 2 parking brake wire assembly) connectors.
    4. Check both the connector case and the terminals for deformation and corrosion.

      OK

      No deformation or corrosion.

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

      Standard Resistance

      Tester Connection Condition Specified Condition
      k1-2 (+) - kN1-1 (RL+) Always Below 1 Ω
      k1-2 (+) or kN1-1 (RL+) - Body ground and other terminals Always 10 kΩ or higher
      k1-1 (-) - kN1-2 (RL-) Always Below 1 Ω
      k1-1 (-) or kN1-2 (RL-) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE NO. 2 PARKING BRAKE WIRE ASSEMBLY 

    Result: 

    OK 

    See step  12

  12. CHECK HARNESS AND CONNECTOR (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY - NO. 2 PARKING BRAKE WIRE ASSEMBLY) 
    1. Make sure that there is no looseness at the locking part and the connecting part of the connector.

      OK

      The connector is securely connected.

    2. Disconnect the A37 skid control ECU (brake booster with master cylinder assembly) connector.
    3. Check both the connector case and the terminals for deformation and corrosion.

      OK

      No deformation or corrosion.

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

      Standard Resistance

      Tester Connection Condition Specified Condition
      A37-34 (RL+) - kN1-1 (RL+) Always Below 1 Ω
      A37-34 (RL+) or kN1-1 (RL+) - Body ground Always 10 kΩ or higher
      A37-35 (RL-) - kN1-2 (RL-) Always Below 1 Ω
      A37-35 (RL-) or kN1-2 (RL-) - Body ground Always 10 kΩ or higher
      NOTE:

      Check the rear speed sensor LH signal after replacement.

      Refer to TEST MODE PROCEDURE [10/2018 - ]

      HINT: 

      The rear speed sensor LH and rear speed sensor rotor LH are incorporated into the rear axle hub and bearing assembly LH. (for 2WD)

      If the rear speed sensor LH and rear speed sensor rotor LH need to be replaced, replace the rear axle hub and bearing assembly LH. (for 2WD)

      Result

      Result Proceed to
      OK (for 2WD) A
      OK (for AWD) B
      NG C

    Result: 

    A 

    REPLACE REAR AXLE HUB AND BEARING ASSEMBLY LH. Refer to  REMOVAL [10/2018 - 07/2022]  , or refer to  REMOVAL [07/2022 - ] 

    Result: 

    C 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    B 

    See step  13

  13. CHECK REAR SPEED SENSOR ROTOR (REAR AXLE HUB AND BEARING ASSEMBLY LH) (CHECK FOR FOREIGN MATTER) 
    1. Remove the rear speed sensor rotor (rear axle hub and bearing assembly LH).

      Refer to REMOVAL [10/2018 - 07/2022] , or refer to REMOVAL [07/2022 - ]

    2. Check the speed sensor rotor.

      OK

      The rotor is free of scratches, oil, and foreign matter.

      NOTE:
      • If there is oil or foreign matter on the speed sensor rotor, clean the speed sensor rotor.
      • If the speed sensor rotor is damaged, replace the speed sensor rotor with a new one.
      • Check the speed sensor signal after cleaning or replacement.

        Refer to TEST MODE PROCEDURE [10/2018 - ]

      HINT: 

      • The rear speed sensor rotor is incorporated into the rear axle hub and bearing assembly LH.
      • If the rear speed sensor rotor needs to be replaced, replace it together with the rear axle hub and bearing assembly LH.

      Result

      Result  Proceed to
      OK  A
      NG (The speed sensor rotor is damaged.)  B
      NG (There is foreign matter on the speed sensor rotor.)  C

    Result: 

    A 

    REPLACE REAR SPEED SENSOR LH. Refer to  REMOVAL [10/2018 - ] 

    Result: 

    B 

    REPLACE REAR AXLE HUB AND BEARING ASSEMBLY LH. Refer to  REMOVAL [10/2018 - 07/2022]  , or refer to  REMOVAL [07/2022 - ] 

    Result: 

    C 

    CLEAN REAR SPEED SENSOR ROTOR (REAR AXLE HUB AND BEARING ASSEMBLY LH) 

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