Last Modified: 04-05-2023 6.11:8.1.0 Doc ID: RM1000000018KF1
Model Year Start: 2018 Model: Sienna Prod Date Range: [11/2017 -           ]
Title: BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: VEHICLE STABILITY CONTROL SYSTEM: C1439,C1445; Steering Angle Sensor Initialization Incomplete; 2018 - 2020 MY Sienna [11/2017 -        ]

DTC

C1439

Steering Angle Sensor Initialization Incomplete

DTC

C1445

Vehicle Driven with Steering Angle Sensor not Initialized

DESCRIPTION

The skid control ECU (brake actuator assembly) acquires steering angle sensor zero point every time the ignition switch turned to ON and the vehicle is driven at 35 km/h (22 mph) or more for approximately 5 seconds. The ECU also stores previous zero points.

The steering angle sensor zero point malfunction warning is canceled by turning the ignition switch is turned off.

DTC No.

DTC Detection Condition

Trouble Area

C1439

After the steering angle sensor zero point calibration is cleared due to, for example, fluctuations in the power source, the steering angle sensor zero point calibration cannot be obtained for 0.048 seconds of continuous driving.

  • Steering angle sensor (Spiral cable with sensor sub-assembly)
  • Yaw rate and acceleration sensor (airbag sensor assembly)

C1445

Steering angle sensor zero point calibration cannot be obtained when the vehicle is driven without a record of steering angle sensor zero point calibration at a speed of 35 km/h (22 mph) or more for 30 seconds or more without the brake pedal being depressed.

  • Steering angle sensor (Spiral cable with sensor sub-assembly)
  • Yaw rate and acceleration sensor (airbag sensor assembly)

CAUTION / NOTICE / HINT

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 voltage drops when the battery is removed, and confirm that this condition occurred.

HINT:

  • When U0073, U0124 and/or U0126 is output together with C1439 and/or C1445, inspect and repair the trouble areas indicated by U0073, U0124 and/or U0126 first (See page 2018 - 2020 MY Sienna [11/2017 -        ]; BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: VEHICLE STABILITY CONTROL SYSTEM: U0073,U0100,U0124,U0126; Control Module Communication Bus OFF ).
  • When a speed sensor or the yaw rate and acceleration sensor (airbag sensor assembly) has trouble, DTCs for the steering angle sensor (spiral cable with sensor sub-assembly) may be stored even when the steering angle sensor (spiral cable with sensor sub-assembly) is normal. When DTCs for the speed sensor or yaw rate and acceleration sensor (airbag sensor assembly) are output together with other DTCs for the steering angle sensor (spiral cable with sensor sub-assembly), inspect and repair the speed sensor and yaw rate and acceleration sensor (airbag sensor assembly) first, and then inspect and repair the steering angle sensor (spiral cable with sensor sub-assembly).

PROCEDURE

1.

CHECK DTC

(a) Clear the DTCs (See page 2018 - 2020 MY Sienna [11/2017 -        ]; BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: VEHICLE STABILITY CONTROL SYSTEM: DTC CHECK / CLEAR ).

(b) Turn the ignition switch off.

(c) Turn the ignition switch to ON again and check that no CAN communication system DTCs are output (See page 2018 MY Sienna [11/2017 - 08/2018]; NETWORKING: CAN COMMUNICATION SYSTEM: DIAGNOSIS SYSTEM 2019 - 2020 MY Sienna [08/2018 -        ]; NETWORKING: CAN COMMUNICATION SYSTEM: DIAGNOSIS SYSTEM ).

(d) Drive the vehicle at a speed of 35 km/h (22 mph) or more and turn the steering wheel to the right and left and check that no speed sensor or yaw rate and acceleration sensor DTCs are output (See page 2018 - 2020 MY Sienna [11/2017 -        ]; BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: VEHICLE STABILITY CONTROL SYSTEM: DTC CHECK / CLEAR ).

Result

Proceed to

DTCs C1439 and/or C1445 are output.

A

CAN communication system DTCs are output.

B

Speed sensor, yaw rate and acceleration sensor and/or steering angle sensor DTCs are output.

C

DTCs C1439 and C1445 are not output.

D

HINT:

  • If there is a malfunction in the speed sensor or the yaw rate and acceleration sensor (airbag sensor assembly), an abnormal value may be output although the steering angle sensor (spiral cable with sensor sub-assembly) is normal.
  • If the speed sensor and the yaw rate and acceleration sensor (airbag sensor assembly) DTCs are output simultaneously, repair the sensors and inspect the steering angle sensor (spiral cable with sensor sub-assembly).
  • If DTC C1439 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 voltage drops.
B

CHECK CAN COMMUNICATION SYSTEM

C

REPAIR CIRCUITS INDICATED BY OUTPUT DTC

D

USE SIMULATION METHOD TO CHECK

A

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 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

(See page 2018 MY Sienna [11/2017 - 08/2018]; ALIGNMENT / HANDLING DIAGNOSIS: FRONT WHEEL ALIGNMENT: ADJUSTMENT 2019 - 2020 MY Sienna [08/2018 -        ]; ALIGNMENT / HANDLING DIAGNOSIS: FRONT WHEEL ALIGNMENT: ADJUSTMENT )

OK

3.

RECONFIRM DTC

(a) Turn the ignition switch off.

(b) Clear the DTCs (See page 2018 - 2020 MY Sienna [11/2017 -        ]; BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: VEHICLE STABILITY CONTROL SYSTEM: DTC CHECK / CLEAR ).

(c) Turn the ignition switch off.

(d) Start the engine.

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

(f) Check if the same DTC is output (See page 2018 - 2020 MY Sienna [11/2017 -        ]; BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: VEHICLE STABILITY CONTROL SYSTEM: DTC CHECK / CLEAR ).

Result

Proceed to

DTCs C1439 and C1445 are not output.

A

Yaw rate and acceleration sensor and/or steering angle sensor DTCs are output.

B

HINT:

If DTC C1439 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 voltage drops.

A

END

B

REPAIR CIRCUITS INDICATED BY OUTPUT DTC