C1231

BRAKE CONTROL: ELECTRONICALLY CONTROLLED BRAKE SYSTEM: C1231/31: Steering Angle Sensor Circuit Malfunction

DTC C1231/31 - Steering Angle Sensor Circuit Malfunction

DESCRIPTION

The steering angle sensor signal is sent to the skid control ECU via the CAN communication system. When there is a malfunction in the CAN communication system, it will be detected by the diagnosis function.






WIRING DIAGRAM





INSPECTION PROCEDURE
HINT:
- When U0073/94, U0293/59, U0123/62, U0124/95, U0126/63, U0130/68 or U0131/67 is output together with C1231/31, inspect and repair the trouble areas indicated by U0073/94, U0293/59, U0123/62, U0124/95, U0126/63, U0130/68 or U0131/67 first.
- When the speed sensor or the yaw rate 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 sensor first, and then inspect and repair the steering angle sensor.

PROCEDURE

1. CHECK HARNESS AND CONNECTOR (MOMENTARY INTERRUPTION)
(a) Using the Techstream, check for any momentary interruption in the wire harness and connectors between the skid control ECU and the steering angle sensor Check For Intermittent Problems.

ABS / VSC / TRAC:





OK:
There are no momentary interruptions.
HINT: Perform the above inspection before removing the sensor and connector.

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (STEERING ANGLE SENSOR TO SKID CONTROL ECU)
OK -- Continue to next step.
2. CHECK DTC
(a) Clear the DTC Reading and Clearing Diagnostic Trouble Codes.
(b) Turn the power switch OFF.
(c) Turn the power switch ON (IG) again and check that no CAN communication system DTC is output.
(d) Drive the vehicle and turn the steering wheel to the right and left at a speed of 35 km/h (24 mph) and check that no speed sensor and yaw rate sensor DTCs are output.

Result





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

C -- REPAIR CIRCUIT INDICATED BY OUTPUT CODE
B -- REPAIR CAN COMMUNICATION SYSTEM
A -- Continue to next step.
3. CHECK WIRE HARNESS (STEERING ANGLE SENSOR - BODY GROUND)





(a) Remove the steering wheel and the column cover lower.
(b) Disconnect the K19 sensor connector.
(c) Measure the voltage according to the value(s) in the table below.
Standard voltage:





(d) Measure the resistance according to the value(s) in the table below.
Standard resistance:





HINT: If troubleshooting has been carried out according to the "PROBLEM SYMPTOMS TABLE", refer back to the table and proceed to the next step Problem Symptoms Table.

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (IG, BAT OR ESS CIRCUIT)
OK -- REPLACE STEERING ANGLE SENSOR
4. REPAIR OR REPLACE HARNESS OR CONNECTOR (STEERING ANGLE SENSOR TO SKID CONTROL ECU)
NEXT -- Continue to next step.
5. RECONFIRM DTC
(a) Clear the DTC Reading and Clearing Diagnostic Trouble Codes.
(b) Turn the power switch ON (READY).
(c) Drive the vehicle and turn the steering wheel to the right and left at a speed of 35 km/h (24 mph) or more.
(d) Check if the same DTC is recorded Reading and Clearing Diagnostic Trouble Codes.

Result





HINT: If troubleshooting has been carried out according to the "PROBLEM SYMPTOMS TABLE", refer back to the table and proceed to the next step Problem Symptoms Table.

B -- CHECK DTC
A -- END