Toyota Tundra. Manual — part 944

If this DTC is output, clear the zero point calibration data and enter test mode (See TEST MODE
PROCEDURE ). The system returns to normal when the correct data is received from the ECM.

INSPECTION PROCEDURE

1. REPLACE ECM

a. Replace the ECM for 1GR-FE (See REMOVAL ), (See REMOVAL 2UZ-FE) or (See REMOVAL

3UR-FE).

2. RECONFIRM DTC

a. Clear the DTC (See DTC CHECK/CLEAR ).

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

Result

RESULT TABLE

B: END

A: REPLACE VSC ACTUATOR ASSEMBLY (See REMOVAL )

DTC C1439/66 , C1445/66 STEERING ANGLE SENSOR INITIALIZATION INCOMPLETE;
VEHICLE DRIVEN WITH STEERING ANGLE SENSOR NOT INITIALIZED

DESCRIPTION

The skid control ECU acquires the steering angle sensor zero point every time the ignition switch is turned to
ON 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 will be canceled by turning the ignition switch off.

DTC DETECTION CONDITION TABLE

NOTE:

When replacing the VSC actuator assembly, perform zero point calibration (See
CALIBRATION ).

Result

Proceed to

DTC is output

A

DTC is not output

B

DTC Code

DTC Detection Condition

Trouble Area

C1439/66

After the steering angle sensor
zero point calibration data is
cleared due to, for example,
fluctuations in the power source,
the steering angle zero point is not
obtained after 60 seconds of



Steering angle sensor



Yaw rate and deceleration
sensor



VSC actuator assembly (Skid
control ECU)

2009 Toyota Tundra

2009 BRAKES Brake Control - Tundra

WIRING DIAGRAM

Fig. 87: Identifying Steering Angle Sensor CAN Line - Wiring Diagram
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

continuous driving

C1445/66

Steering angle sensor zero point is
not obtained when the vehicle is
driven without a record of steering
angle sensor zero point calibration
at a speed of 36 km/h (22 mph) or
more for 30 seconds or more
without the brake pedal being
depressed



Steering angle sensor



Yaw rate and deceleration
sensor



VSC actuator assembly (Skid
control ECU)

2009 Toyota Tundra

2009 BRAKES Brake Control - Tundra

Fig. 88: Identifying Yaw Rate, Deceleration Sensor & Skid Control ECU - Wiring Diagram
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

INSPECTION PROCEDURE

1. CHECK DTC

a. Clear the DTC (See DTC CHECK/CLEAR ).

b. Turn the ignition switch off.

NOTE:



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 data, such as when the power source voltage drops when the
battery is removed, and confirm whether this condition occurred.



When U0073/94, U0123/62, U0124/69 and/or U0126/63 is output together
with C1231/31, inspect and repair the trouble areas indicated by U0073/94,
U0123/62, U0124/69 and/or U0126/63 first. (See DTC U0073/94, U0100/65,
U0114/27, U0123/62, U0124/69, U0126/63)



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 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 TABLE)



When the steering angle sensor and/or yaw rate and deceleration sensor is
replaced, perform zero point calibration for the applicable sensor(s). (See
CALIBRATION)



When replacing the VSC actuator assembly, perform zero point calibration.
(See CALIBRATION)

2009 Toyota Tundra

2009 BRAKES Brake Control - Tundra

c. Turn the ignition switch to ON again and check that no CAN communication system DTC is

output.

d. Drive the vehicle at a speed of 36 km/h (22 mph), turn the steering wheel to the right and left and

check that no speed sensor or yaw rate and deceleration sensor DTCs are output (See DTC
CHECK/CLEAR).

RESULT TABLE

HINT:



If there is a malfunction in the speed sensor or the yaw rate and deceleration sensor, a DTC 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 then 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 data, such as when the power
source voltage drops.

D: CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION)

C: REPAIR CIRCUITS INDICATED BY OUTPUT DTCS

B: GO TO CAN COMMUNICATION SYSTEM (SeeCAN COMMUNICATION SYSTEM )

A: GO 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 deceleration sensor zero point again after
the adjustments are completed.

OK: The centered position of the steering wheel is correctly set.

NEXT Go to step 3.

3. RECONFIRM DTC

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

Result

Proceed to

DTC (C1439/66 and/or C1445/66) output

A

DTC output (relating to CAN communication system)

B

DTC output (relating to speed sensor or yaw rate and deceleration

sensor)

C

DTC not output

D

2009 Toyota Tundra

2009 BRAKES Brake Control - Tundra