DTC U0073: Control Module Communication Bus Off; DTC U0100: Lost Communication with ECM / PCM "A"; DTC U0129: Lost Communication with Brake System Control Module: Description

The 4WD 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
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