DTC U0122: Lost Communication With Vehicle Dynamics Control Module: General Description

CAN (Controller Area Network) communication is a communication system for electronic control units in a vehicle that is designed to connect individual control modules inside the vehicle (engine, transmission, 4WD ECU, ABS/ESP, etc) using two lines, High and Low, to share information within the system. The DEHA (Direct Electro-Hydraulic Actuator) 4WD system receives CAN signals (engine torque, gear shift range, accelerator pedal sensor, wheel speed, automatic control, etc) from other control units and optimizes 4WD torque distribution depending on operational conditions of the vehicle. If any signals essential to the 4WD ECU are not transmitted or an error occurs in the CAN communication system, then the 4WD ECU identifies CAN signal failures and stores the error code.