VEHICLE STABILITY CONTROL SYSTEM, Diagnostic DTC:C1231

DTC Code DTC Name
C1231 Steering Angle Sensor Circuit

DESCRIPTION

The skid control ECU (brake actuator assembly) receives steering angle sensor signals via CAN communication. When a malfunction occurs in the communication line with the steering angle sensor, DTC U0126 (Lost Communication with Steering Angle Sensor Module) is stored.

DTC No. Detection Item DTC Detection Condition Trouble Area
C1231 Steering Angle Sensor Circuit While steering angle sensor communication is enabled, a malfunction signal output is received during the sensor self check (sensor malfunction). Steering angle sensor internal malfunction

WIRING DIAGRAM

B0070SUE05

CAUTION / NOTICE / HINT

Note

Inspect the fuses for circuits related to this system before performing the following procedure.

Tech Tips


  • When U0126 is output together with C1231, inspect and repair the trouble areas indicated by U0126 first.

    Click here

  • When a speed sensor or yaw rate and acceleration sensor (airbag sensor assembly) is malfunctioning, DTCs for the steering angle sensor may be output even when the steering angle sensor is normal. When DTCs for a speed sensor or the yaw rate and acceleration sensor (airbag sensor assembly) are output together with DTCs for the steering angle sensor, inspect and repair the speed sensor and yaw rate and acceleration sensor (airbag sensor assembly) first, and then inspect and repair the steering angle sensor.

PROCEDURE


  1. CHECK DTC


    1. Clear the DTCs.


      Chassis > ABS/VSC/TRC > Clear DTCs

    2. Turn the ignition switch off.

    3. Turn the ignition switch to ON again and check that no CAN communication system DTCs are output.

      Click here

    4. Drive the vehicle at a speed of 35 km/h (22 mph), turn the steering wheel to the right and left, and check that no speed sensor and/or yaw rate and acceleration sensor DTCs are output.


      Chassis > ABS/VSC/TRC > Trouble Codes
      Result
      Result Proceed to
      C1231 is output A
      CAN communication system DTCs are output B
      Speed sensor and/or yaw rate and acceleration sensor DTCs are output C
      C1231 is not output D

      Tech Tips


      • When CAN communication system DTCs are output, repair the CAN communication system before repairing each corresponding sensor.

      • If there is a malfunction in a speed sensor or the yaw rate and acceleration sensor (airbag sensor assembly), an abnormal value may be output even though the steering angle sensor is normal.

      • If speed sensor and yaw rate and acceleration sensor DTCs are output simultaneously, repair the sensors and inspect the steering angle sensor.


    B

    INSPECT CAN COMMUNICATION SYSTEM Click here

    C

    REPAIR CIRCUITS INDICATED BY OUTPUT DTCS Click here

    D

    USE SIMULATION METHOD TO CHECK Click here

    A

  2. CHECK HARNESS AND CONNECTOR (POWER SOURCE TERMINAL)


    1. B00700KC01
      *a

      Front view of wire harness connector

      (to Steering Angle Sensor)

      Turn the ignition switch off.

    2. Remove the steering wheel and column cover.

    3. Make sure that there is no looseness at the locking part and the connecting part of the connector.

      OK
      The connector is securely connected.

    4. Disconnect the K71 steering angle sensor connector.

    5. Check both the connector case and the terminals for deformation and corrosion.

      OK
      No deformation or corrosion.

    6. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      K71-9 (IG1) - Body ground Ignition switch ON 11 to 14 V
      K71-4 (BAT) - Body ground Always 11 to 14 V
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)

    OK

  3. CHECK HARNESS AND CONNECTOR (GROUND TERMINAL)


    1. B00700KC04
      *a

      Front view of wire harness connector

      (to Steering Angle Sensor)

      Turn the ignition switch off.

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

      Note

      Before measuring the resistance of the steering angle sensor, turn the ignition switch off and leave the vehicle for 1 minute or more without operating the key or switches, or opening or closing the doors.

      Standard Resistance
      Tester Connection Condition Specified Condition
      K71-6 (ESS) - Body ground 1 minute after ignition switch off Below 1 Ω
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE STEERING ANGLE SENSOR Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (GROUND CIRCUIT)