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Home >> Infiniti >> 2024 >> QX55 Essential >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control System (DTC/Circuit Diagnosis) (1 Of 4) >> DTC/Circuit Diagnosis >> U0122 Vehicle Dynamics Control Module >> DTC Description
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DTC Description

CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle multiplex communication line with high data communication speed and excellent error detection ability. Many electronic control units are equipped onto a vehicle, and each control unit shares information and links with other control units during operation (not independent). In CAN communication, control units are connected with 2 communication lines (CAN H line, CAN L line) allowing a high rate of information transmission with less wiring. Each control unit transmits/receives data but selectively reads required data only.

DTC DETECTION LOGIC 

DTC CONSULT screen terms(Trouble diagnosis content) DTC detection condition
U0122 VDC MDL(Lost communication with vehicle dynamics control module) Diagnosis condition Ignition switch ON
Signal (terminal) CAN communication signal
Threshold When ECM is not transmitting or receiving CAN communication signal of OBD (emission related diagnosis) with ABS actuator and electric unit (control unit)
Diagnosis delay time 2 seconds or more

POSSIBLE CAUSE 

Harness or connectors (CAN communication line is open or shorted)

FAIL-SAFE 

Not applicable