Vehicle Stability Control System

BRAKE CONTROL: VEHICLE STABILITY CONTROL SYSTEM: C1439/66, C1445/66: Steering Angle Sensor Initialization Incomplete


DESCRIPTION

The skid control ECU acquires the steering angle sensor zero point every time the engine switch is turned on (IG) and the vehicle is driven at 35 km/h (22 mph) or more for approximately 5 seconds. The ECU also stores previous zero point.

DTCs C1439/66 and C1445/66 will be cleared when the engine switch is turned off.





INSPECTION PROCEDURE

NOTICE:
Before proceeding with the inspection, explain to the customer that the output DTC is related to temporary loss of the steering angle zero point calibration, such as when the power source voltage drops when the battery is removed, and confirm that this condition occurred.

HINT
- When DTC U0073/94, U0123/62, U0124/95 and/or U0126/63 is output together with DTC C1439/66 and/or C1445/66, inspect and repair the trouble areas indicated by DTC U0073/94, U0123/62, U0124/95 and/or U0126/63 first Control Module Communication Bus OFF.
- When the speed sensor or the yaw rate and acceleration 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 and acceleration sensor are output together with other 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 Vehicle Stability Control System.

(b) Turn the engine switch off.

(c) Turn the engine switch on (IG) again and check that no CAN communication system DTCs are output Diagnosis System.

(d) Drive the vehicle and turn the steering wheel to the right and left at a speed of 35 km/h (22 mph) and check that no speed sensor, yaw rate and acceleration sensor and steering angle sensor DTCs are output Vehicle Stability Control System.

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 the speed sensor and the yaw rate and acceleration sensor DTCs are output simultaneously, repair the sensors and inspect the steering angle sensor.
- If the same DTC C1439/66 and/or C1445/66 is not output again, the DTC may have been stored due to a temporary loss of the steering angle zero point calibration, such as when the power source voltage drops.

D -- CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION) Diagnosis System

C -- REPAIR CIRCUIT INDICATED BY OUTPUT DTC Vehicle Stability Control System

B -- INSPECT CAN COMMUNICATION SYSTEM How to Proceed With Troubleshooting
A -- Continue to next step.

2. CHECK STEERING ANGLE SENSOR ZERO POINT CALIBRATION

(a) Drive the vehicle straight ahead at 35 km/h (22 mph) or more for at least 5 seconds.

(b) Check that the steering wheel is centered correctly while driving straight ahead.

HINT
If the front wheel alignment and steering position are adjusted as a result of an off-centered position of the steering wheel, acquire yaw rate and acceleration sensor zero point again after the adjustments are completed.

OK:

The steering wheel is centered correctly.

NG -- ADJUST FRONT WHEEL ALIGNMENT OR STEERING POSITION Front Wheel Alignment
OK -- Continue to next step.

3. RECONFIRM DTC

(a) Turn the engine switch off.

(b) Clear the DTCs Vehicle Stability Control System.

(c) Start the engine.

(d) Drive the vehicle and turn the steering wheel to the right and left at the speed of 35 km/h (22 mph) or more.

(e) Check if the same DTC is recorded Vehicle Stability Control System.

Result:





HINT
- If the same DTC C1439/66 and/or C1445/66 is not output again, the DTC may have been stored due to a temporary loss of the steering angle zero point calibration, such as when the power source voltage drops.
- If the same DTC C1439 and/or C1445 is not output again, the DTC may have been stored due to a temporary loss of the steering angle zero point calibration, such as when the power source voltage drops.
- 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.

B -- REPAIR CIRCUIT INDICATED BY OUTPUT DTC Vehicle Stability Control System

A -- END