DTC U2121-00: Can Communication System: Communication Error With Vehicle Control Module (VCM)

U2121-00: (PCM - SKYACTIV-G) DETECTION CONDITION AND POSSIBLE CAUSE

System malfunction location	CAN communication system: Communication error with vehicle control module (VCM)
Detection condition	A communication error between the PCM and the vehicle control module (VCM) continues for the specified time.
Fail-safe	Inhibits engine-stop by i-stop control.
Possible cause	Malfunction in CAN communication line between vehicle control module (VCM) and PCM NOTE: Perform the malfunction diagnosis according to the troubleshooting procedure for the multiplex communication system. (See MALFUNCTION DIAGNOSIS FLOW [CONTROLLER AREA NETWORK (CAN)] .) Vehicle control module (VCM) malfunction (built into body control module (BCM)) (Refer to BODY CONTROL MODULE (BCM) REMOVAL/INSTALLATION in service information.) PCM malfunction (Refer to PCM REMOVAL/INSTALLATION in service information.)
Repeatability verification procedure	Not applicable
System wiring diagram	Not applicable