MF1A (TRANSFER / 4WD / AWD): ACTIVE TORQUE CONTROL 4WD SYSTEM: U0073,U0100,U0126,U0129; Control Module Communication Bus OFF; 2017 - 2020 MY Sienna [08/2016

Last Modified: 04-05-2023	6.11:8.1.0	Doc ID: RM10000000103R7
Model Year Start: 2017	Model: Sienna	Prod Date Range: [08/2016 - ]
Title: MF1A (TRANSFER / 4WD / AWD): ACTIVE TORQUE CONTROL 4WD SYSTEM: U0073,U0100,U0126,U0129; Control Module Communication Bus OFF; 2017 - 2020 MY Sienna [08/2016 - ]

DTC

U0073

Control Module Communication Bus OFF

DTC

U0100

Lost Communication with ECM / PCM "A"

DTC

U0126

Lost Communication with Steering Angle Sensor Module

DTC

U0129

Lost Communication with Brake System Control Module

DESCRIPTION

The 4WD control ECU inputs the signals sent from the ECM and skid control ECU via the CAN communication system.
When DTCs indicating a CAN communication system malfunction are output, repair the CAN communication system before repairing each corresponding sensor.

DTC No.	DTC Detection Condition	Trouble Area
U0073	When the following continues for 5 seconds or more: - Signals from the 4WD control ECU are not received. When the following occurs 10 times consecutively: - A communication malfunction (bus off) occurs one or more times within 0.1 seconds.	CAN communication system
U0100	When both of the following continue for 2 seconds or more: - The voltage of the IG1 terminal is 10 V or more. - At a vehicle speed of 60 km/h (38 mph) or more, communication with the ECM cannot be performed.	CAN communication system
U0126	When both of the following continue for 1 second or more: - The voltage of the IG1 terminal is 10 V or more. - Communication with the steering angle sensor cannot be performed. When all of the following occur 10 times consecutively: - The condition that communication with the steering angle sensor cannot be performed occurs once within 5 seconds. - The voltage of the IG1 terminal is 10 V or more. - Occurs 10 times or more within 60 seconds.	CAN communication system
U0129	When the following continues for 3 seconds or more: - The voltage of the IG1 terminal is 10 V or more. - Communication with the skid control ECU cannot be performed.	CAN communication system

PROCEDURE

1.	CHECK FOR DTC (ACTIVE TORQUE CONTROL 4WD SYSTEM)

(a) Check for DTCs (See page ).

(b) Record the output DTCs (active torque control 4WD system).

HINT:

When DTCs indicating a CAN communication system malfunction are output, repair the CAN communication system before repairing each corresponding sensor.

GO TO CAN COMMUNICATION SYSTEM

(See page )