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DTC    C1231/31    Steering Angle Sensor Circuit Malfunction

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DESCRIPTION

The skid control ECU inputs the steering angle sensor signal through the CAN communication. When a malfunction occurs in the communication line with the steering angle sensor, DTC U0126/63 (malfunction in communication with steering angle sensor) is output.

DTC No.
INF Code
DTC Detecting Condition
Trouble Area
C1231/31
-
  1. Steering angle sensor malfunction signal is received when data transmission is valid (internal malfunction is detected at sensor self-check).
  2. A signal of +B open in steering angle sensor is received when communication with sensor is valid.
  1. Steering angle sensor
  2. Steering angle sensor circuit
  3. Steering angle sensor power supply
  4. Skid control ECU

WIRING DIAGRAM


C100604E02


INSPECTION PROCEDURE

HINT:
  1. When U0126/63 is output together with C1231/31, inspect and repair the trouble areas indicated by U0126/63 first.
  2. When the speed sensor or the yaw rate and deceleration sensor has trouble, DTCs for the steering angle sensor may be output even when the steering angle sensor is normal. When DTCs for the speed sensor or yaw rate sensor are output together with other DTCs for the steering angle sensor, inspect and repair the speed sensor and yaw rate and deceleration sensor first, and then inspect and repair the steering angle sensor.

1.CHECK HARNESS AND CONNECTOR (MOMENTARY INTERRUPTION)

  1. Using the intelligent tester, check for any momentary interruption in the wire harness and connectors between the skid control ECU and steering angle sensor (Click here).

    ABS / VSC / TRAC: 
    Item
    		Measurement Item /
    Range (Display)
    		Normal Condition
    Steering Open
    		Steering sensor open detection /
    NORMAL or ERROR
    		NORMAL : Normal condition

    OK:
    There are no momentary interruptions.



NG
Go to step 4
OK


2.CHECK STEERING SENSOR

  1. Clear the DTC (Click here).

  1. Turn the ignition switch off.

  1. Turn the ignition switch to the ON position again and check that no CAN communication system DTC is output (Click here).

  1. Drive the vehicle and turn the steering wheel to the right and left (Drive and steer the vehicle) at the speed of 35 km/h (24 mph) and check that no speed sensor and yaw rate sensor DTCs are output.

    Result:

    Condition
    		Proceed To
    No CAN communication system DTC and the speed sensor or yaw rate sensor DTC are output.
    		A
    CAN communication system DTC is output.
    		B
    Speed sensor or yaw rate sensor DTC is output.
    		C

    HINT:
    1. If there is a malfunction in the speed sensor or the yaw rate sensor an abnormal value may be output although the steering sensor is normal.
    2. If the speed sensor and the yaw rate sensor DTCs are output simultaneously, repair the sensors and inspect the steering sensor.



B
REPAIR CAN COMMUNICATION SYSTEM ACCORDING TO OUTPUT CODE

C
REPAIR CIRCUIT INDICATED BY OUTPUT CODE
A


3.INSPECT STEERING ANGLE SENSOR (IG, BAT AND ESS TERMINAL)


    G026292E01

  1. Remove the steering wheel and the column lower cover.

  1. Disconnect the steering angle sensor connector.

  1. Turn the ignition switch on.

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

    Voltage:
    Tester Connection
    		Specified Condition
    S10-1 (IG1) - S10-2 (ESS)
    		10 to 14 V

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

    Voltage:
    Tester Connection
    		Specified Condition
    S10-3 (BAT) - S10-2 (ESS)
    		10 to 14 V



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

REPLACE STEERING ANGLE SENSOR 

4.REPAIR OR REPLACE HARNESS OR CONNECTOR (BETWEEN STEERING ANGLE SENSOR AND SKID CONTROL ECU)

NEXT


5.RECONFIRM DTC

  1. Clear the DTC (Click here).

  1. Turn the ignition switch on.

  1. Drive the vehicle and turn the steering wheel to the right and left at the speed of 35 km/h (24 mph) or more.

  1. Check that the same DTC is recorded (Click here).

    Result:

    Condition
    		Proceed To
    DTC is not output
    		A
    DTC is output
    		B



B
Go to step 2
A

END