Steering Angle Sensor Circuit Malfunction

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

DESCRIPTION

The skid control ECU receives steering angle sensor signals via the CAN communication system. When a malfunction occurs in the communication line with the steering angle sensor, DTC U0126/63 (Lost Communication with Steering Angle Sensor Module) is stored.





WIRING DIAGRAM





INSPECTION PROCEDURE

HINT
* When U0126/63 is output together with C1231/31, inspect and repair the trouble areas indicated by U0126/63 first Electronically Controlled Brake System.
* When a speed sensor, yaw rate and acceleration sensor (for separate type) or yaw rate and acceleration sensor (airbag sensor assembly) (for built-in type) 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, yaw rate and acceleration sensor (for separate type) or yaw rate and acceleration sensor (airbag sensor assembly) (for built-in type) are output together with DTCs for the steering angle sensor, inspect and repair the speed sensor, yaw rate and acceleration sensor (for separate type) and/or yaw rate and acceleration sensor (airbag sensor assembly) (for built-in type) first, and then inspect and repair the steering angle sensor.

PROCEDURE

1. CHECK DTC

(a) Clear the DTCs 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 Diagnosis System.

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

Result:





HINT
* When DTCs indicating CAN communication system malfunctions are output, repair the CAN communication system before repairing each corresponding sensor.
* If there is a malfunction in the speed sensor, yaw rate and acceleration sensor (for separate type) or yaw rate and acceleration sensor (airbag sensor assembly) (for built-in type), an abnormal value may be output although the steering angle sensor is normal.
* If speed sensor and the yaw rate and acceleration sensor DTCs are output simultaneously, repair the sensors and inspect the steering angle sensor.

B -- INSPECT CAN COMMUNICATION SYSTEM How to Proceed With Troubleshooting

C -- REPAIR CIRCUITS INDICATED BY OUTPUT DTCS Electronically Controlled Brake System

D -- CHECK FOR INTERMITTENT PROBLEMS How To Proceed With Troubleshooting
A -- Continue to next step.

2. CHECK HARNESS AND CONNECTOR (POWER SOURCE TERMINAL)

(a) Turn the power switch off.





(b) Remove the steering wheel and the column cover.

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

(d) Disconnect the steering angle sensor connector.

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

Standard Voltage:





Text in Illustration





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)
OK -- Continue to next step.

3. CHECK HARNESS AND CONNECTOR (GROUND TERMINAL)

(a) Turn the power switch off.





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

Standard Resistance:





Text in Illustration





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

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (GROUND CIRCUIT)

OK -- REPLACE STEERING ANGLE SENSOR Removal