Inspection Procedure

NOTE:

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 U0073, U0123, U0124 and/or U0126 is output together with C1439 and/or C1445, inspect and repair the trouble areas indicated by U0073, U0123, U0124 and/or U0126 first (See DTC U0073 CONTROL MODULE COMMUNICATION BUS OFF; DTC U0100 LOST COMMUNICATION WITH ECM / PCM; DTC U0123 LOST COMMUNICATION WITH YAW RATE SENSOR MODULE; DTC U0124 LOST COMMUNICATION WITH LATERAL ACCELERATION SENSOR MODULE; DTC U0126 LOST COMMUNICATION WITH STEERING ANGLE SENSOR MODULE ).
When the speed sensor or the yaw rate and deceleration 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 deceleration sensor are output together with other DTCs for the steering angle sensor, inspect and repair the speed sensor and yaw rate and deceleration sensor first, and then inspect and repair the steering angle sensor (See DIAGNOSTIC TROUBLE CODE CHART ).
When the steering angle sensor and/or yaw rate sensor assembly is replaced, perform zero calibration for the applicable sensor(s) (See TEST MODE PROCEDURE ).
When replacing the brake actuator assembly, perform zero point calibration (See CALIBRATION ).

CHECK DTC

Clear the DTC (See DTC CHECK / CLEAR ).
Turn the ignition switch off.
Turn the ignition switch to ON again and check that no CAN communication system DTC is output.
Drive the vehicle at a speed of 36 km/h (22 mph) and turn the steering wheel to the right and left and check that no speed sensor and yaw rate and deceleration sensor DTCs are output (See DTC CHECK / CLEAR ).

Result

RESULT CHART

Result		Proceed to
DTC is output.	C1439 or/and C1445	A
	Relating to CAN communication system	B
	Relating to speed sensor or yaw rate and deceleration sensor	C
DTC is not output.		D

HINT:

If there is a malfunction in the speed sensor or the yaw rate and deceleration sensor, an abnormal value may be output although the steering angle sensor is normal.
If the speed sensor and the yaw rate and deceleration sensor DTCs are output simultaneously, repair the sensors and inspect the steering angle sensor.
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 : GO TO CAN COMMUNICATION SYSTEM (See DIAGNOSTIC TROUBLE CODE CHART )

C : REPAIR CIRCUITS INDICATED BY OUTPUT DTCS (See DIAGNOSTIC TROUBLE CODE CHART )

D : CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION) (See HOW TO PROCEED WITH TROUBLESHOOTING )

A : Go to Next Step

PERFORM STEERING ANGLE SENSOR ZERO POINT CALIBRATION
1. Drive the vehicle straight ahead at 40 km/h (25 mph) or more for at least 10 seconds.
2. Check that the centered position of the steering wheel is correctly set while driving straight ahead.
  HINT:
  
  If front wheel alignment and steering position are adjusted as a result of abnormal centered position of the steering wheel, acquire yaw rate and deceleration sensor zero point again after the adjustments are completed.
  
  OK: The centered position of the steering wheel is correctly set.
  
  NEXT

RECONFIRM DTC

Check if the same DTC is output (See DTC CHECK / CLEAR ).

Result

RESULT CHART

Result	Proceed to
DTC is output.	A
DTC is not output.	B

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 : END

A : Go to Next Step

READ VALUE USING TECHSTREAM (MOMENTARY INTERRUPTION)

Using the Techstream, check for any momentary interruption in the wire harness and connector corresponding to the DTC (See CHECK FOR INTERMITTENT PROBLEMS ).

ABS/VSC/TRAC

ABS/VSC/TRAC REFERENCE CHART

Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
Yaw Rate Open	Yaw rate sensor open detection / ERROR or NORMAL	ERROR: Momentary interruption NORMAL: Normal	-
Deceleration Open	Deceleration sensor open detection / ERROR or NORMAL	ERROR: Momentary interruption NORMAL: Normal	-
Steering Open	Steering angle sensor open detection / ERROR or NORMAL	ERROR: Momentary interruption NORMAL: Normal	-

OK: There are no momentary interruptions

HINT:

Perform the above inspection before removing the sensor and connector.

NG : Go to step 8

OK : Go to Next Step

REPLACE STEERING ANGLE SENSOR
1. Replace the steering angle sensor (See REMOVAL ).
NEXT
PERFORM STEERING ANGLE SENSOR ZERO POINT CALIBRATION
1. Drive the vehicle straight ahead at 40 km/h (25 mph) or more for at least 10 seconds.
2. Check that the centered position of the steering wheel is correctly set while driving straight ahead.
  HINT:
  
  If front wheel alignment and steering position are adjusted as a result of abnormal centered position of the steering wheel, acquire yaw rate and deceleration sensor zero point again after the adjustments are completed.
  
  OK: The centered position of the steering wheel is correctly set.
  
  NEXT

RECONFIRM DTC

Clear the DTC (See DTC CHECK / CLEAR ).
Start the engine.
Drive the vehicle at a speed of 36 km/h (22 mph) or more and turn the steering wheel to the right and left.
Check if the same DTC is output (See DTC CHECK / CLEAR ).

Result

RESULT CHART

Result	Proceed to
DTC is output.	A
DTC Is not output.	B

B : END

A : REPLACE BRAKE ACTUATOR ASSEMBLY (See REMOVAL )

REPAIR OR REPLACE HARNESS OR CONNECTOR (SKID CONTROL ECU - YAW RATE SENSOR/STEERING ANGLE SENSOR)
1. Turn the ignition switch off.
2. Repair or replace the harness or connector.
3. Check for any momentary interruption between the skid control ECU and yaw rate and deceleration sensor/ steering angle sensor (See CHECK FOR INTERMITTENT PROBLEMS ).
NEXT

RECONFIRM DTC

Clear the DTC (See DTC CHECK / CLEAR ).
Start the engine.
Drive the vehicle at a speed of 36 km/h (22 mph) or more and turn the steering wheel to the right and left.
Check if the same DTC is output (See DTC CHECK / CLEAR ).

Result

RESULT CHART

Result	Proceed to
DTC is output.	A
DTC is not output.	B

B : END

A : Go to Next Step

REPLACE STEERING ANGLE SENSOR
1. Replace the steering angle sensor (See REMOVAL ).
NEXT
PERFORM STEERING ANGLE SENSOR ZERO POINT CALIBRATION
1. Drive the vehicle straight ahead at 40 km/h (25 mph) or more for at least 10 seconds.
2. Check that the centered position of the steering wheel is correctly set while driving straight ahead.
  HINT:
  
  If front wheel alignment and steering position are adjusted as a result of abnormal centered position of the steering wheel, acquire yaw rate and deceleration sensor zero point again after the adjustments are completed.
  
  OK: The centered position of the steering wheel is correctly set.
  
  NEXT

RECONFIRM DTC

Clear the DTC (See DTC CHECK / CLEAR ).
Start the engine.
Drive the vehicle at a speed of 35 km/h (22 mph) or more and turn the steering wheel to the right and left.
Check if the same DTC is output (See DTC CHECK / CLEAR ).

Result

RESULT CHART

Result	Proceed to
DTC is output.	A
DTC is not output.	B

B : END

A : REPLACE BRAKE ACTUATOR ASSEMBLY (See REMOVAL )