DTC Detection Logic

DTC DETECTING CONDITION AND POSSIBLE CAUSE

DTC No.	Trouble diagnosis name	DTC detecting condition	Possible cause
U0400	Invalid data received from hybrid vehicle control ECU	SUM data on CAN signal of OBD (emission related diagnosis) from HV ECU is different from SUM data calculated by ECM.	Harness or connectors (HEV SYSTEM CAN communication line is open or shorted) ECM HV ECU
U1021	Invalid data received from hybrid vehicle control ECU	SUM data on CAN signal other than OBD (emission related diagnosis) from HV ECU is different from SUM data calculated by ECM.