Steering Angle Sensor Circuit Malfunction - Electronically Controlled Brake System

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

DTC C1231/31 - Steering Angle Sensor Circuit Malfunction

DESCRIPTION

The skid control ECU inputs steering angle sensor signals via 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.






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 the speed sensor or the yaw rate and acceleration sensor are malfunctioning, 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 and acceleration sensor are output together with DTCs for the steering angle sensor, inspect and repair the speed sensor and yaw rate and acceleration sensor first, and then inspect and repair the steering angle sensor.

PROCEDURE

1. CHECK DTC
(a) Clear the DTCs.
(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 and turn the steering wheel to the right and left at the speed of 35 km/h (22 mph) and check that no speed sensor and/or 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 speed sensor and yaw rate sensor DTCs are output simultaneously, repair these two sensors and inspect the steering angle sensor.

C -- REPAIR CIRCUIT INDICATED BY OUTPUT DTC
B -- INSPECT CAN COMMUNICATION SYSTEM
A -- Continue to next step.
2. INSPECT STEERING ANGLE SENSOR (POWER SOURCE TERMINAL)





(a) Turn the power switch off.
(b) Remove the steering wheel and the column cover lower.
(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:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)
OK -- Continue to next step.
3. INSPECT STEERING ANGLE SENSOR (GROUND TERMINAL)





(a) Turn the power switch off.
(b) 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 (GROUND CIRCUIT)
OK -- REPLACE STEERING ANGLE SENSOR