C1445
BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: VEHICLE STABILITY CONTROL SYSTEM: C1439, C1445: Steering Angle Sensor Initialization Incomplete
DESCRIPTION
The skid control ECU acquires steering angle sensor zero point every time the engine switch is turned on (IG) and the vehicle is driven at 40 km/h (25 mph) or more for approximately 10 seconds. The ECU also stores the previous zero point.
The steering angle sensor zero point malfunction warning is canceled by turning the engine switch 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 calibration, such as when the power voltage drops when the battery is removed, and confirm that this condition occurred.
- When replacing the master cylinder solenoid, perform calibration Programming and Relearning.
HINT
- When DTC U0073, U0123, U0124 and/or U0126 is output together with DTC C1439 and/or C1445, inspect and repair the trouble areas indicated by DTC U0073, U0123, U0124 and/or U0126 first U0073.
- When the speed sensor or the yaw rate and acceleration sensor has trouble, DTCs for the steering angle sensor may be stored 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 Reading and Clearing Diagnostic Trouble Codes.
(b) Turn the engine switch off.
(c) Turn the engine switch on (IG) again and check that no CAN communication system DTC is output.
(d) Drive the vehicle at a speed of 40 km/h (25 mph) and turn the steering wheel to the right and left, and then check that no speed sensor and 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 the speed sensor and the yaw rate and acceleration sensor DTCs are output simultaneously, repair the sensors and inspect the steering angle sensor.
- If 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 calibration, such as when the power voltage drops.
D -- USE SIMULATION METHOD TO CHECK How To Proceed With Troubleshooting
C -- REPAIR CIRCUITS INDICATED BY OUTPUT DTCS Vehicle Stability Control System
B -- GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING) How to Proceed With Troubleshooting
A -- Continue to next step.
2. PERFORM STEERING ANGLE SENSOR ZERO POINT CALIBRATION
(a) Drive the vehicle straight ahead at 40 km/h (25 mph) or more for at least 10 seconds.
(b) Check that the centered position of the steering wheel is correctly set while driving straight ahead.
HINT
If the front wheel alignment and steering position are adjusted as a result of an abnormal centered position of the steering wheel, acquire the yaw rate and acceleration sensor zero point again after the adjustments are completed.
OK:
The centered position of the steering wheel is correctly set.
NG -- ADJUST FRONT WHEEL ALIGNMENT OR STEERING POSITION Front Wheel Alignment
OK -- Continue to next step.
3. RECONFIRM DTC
(a) Clear the DTC Reading and Clearing Diagnostic Trouble Codes.
(b) Turn the engine switch off.
(c) Start the engine.
(d) Drive the vehicle at a speed of 40 km/h (25 mph) or more and turn the steering wheel to the right and left.
(e) Check if the same DTC is output Reading and Clearing Diagnostic Trouble Codes.
Result
HINT
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 calibration, such as when the power voltage drops.
B -- REPAIR CIRCUITS INDICATED BY OUTPUT DTCS Vehicle Stability Control System
A -- END