Steering Angle Sensor Circuit Malfunction - Electronically Controlled Brake System

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

DESCRIPTION

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





WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
Inspect the fuses for circuits related to this system before performing the following 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 the yaw rate and acceleration sensor are output together with DTCs for the steering angle sensor, inspect and repair the speed sensor and the yaw rate and acceleration sensor 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 ignition switch off.

(c) Turn the ignition switch to ON again and check that no CAN communication system DTC is output (w/ Smart Key System: Diagnosis System, w/o Smart Key System: Diagnosis System).

(d) 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 Reading and Clearing Diagnostic Trouble Codes.

Result:





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

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

C -- GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING) How to Proceed With Troubleshooting

B -- GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING) How to Proceed With Troubleshooting
A -- Continue to next step.

2. INSPECT STEERING ANGLE SENSOR (POWER SOURCE TERMINAL)

(a) Turn the ignition 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:





Text in Illustration





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 ignition 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 suspected area Problem Symptoms Table.

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

OK -- REPLACE STEERING ANGLE SENSOR Removal