DTC U0074-00: Can Communication: Module Communication Error (At-Bus)

WARNING: <<High voltage>>

If the necessary measures are not taken before servicing an electric vehicle, it could cause electrical shock and result in serious injury or, in the worst case, death. Before servicing the electric vehicle, refer to [HIGH VOLTAGE SERVICE CAUTIONS ] in the general information and implement the necessary measures. (Refer to [HIGH VOLTAGE SERVICE CAUTIONS ] in service information).

U0074:00 (TCM (PM8AX-EC)) DETECTION CONDITION AND POSSIBLE CAUSE

System malfunction location	CAN communication: Module communication error (AT-bus)
Detection condition	Malfunction in CAN bus communication line. Precondition Lead-acid battery voltage is the standard or more.
Fail-safe	Not applicable
Possible cause	WARNING: <<High voltage>> If necessary measures such as wearing the correct protective gear are not taken when inspecting or removing/installing the high voltage parts, it could cause electrical shock and result in serious injury or, in the worst case, death. Before inspecting or removing/installing the high voltage parts, refer to [HIGH VOLTAGE SERVICE CAUTIONS ] in the general information and [High Voltage Part Inspection and Removal/Installation Notes] of the high voltage system service cautions and implement the necessary measures and preparations. (Refer to [HIGH VOLTAGE SERVICE CAUTIONS ] in service information). (Refer to [HIGH VOLTAGE SYSTEM SERVICE CAUTIONS ] in service information). Wear insulated gloves when working on a high voltage system. DTCs are stored in the following modules. ECM (See DTC TABLE [ECM (e-SKYACTIV PHEV)] .) PCM (See DTC TABLE [PCM (e-SKYACTIV PHEV)] .) Selector lever (See DTC TABLE [ECL] .) Backup power supply unit (See DTC TABLE [BPS] .) Drive motor control module (See DTC TABLE [SGC2/DMCM (e-SKYACTIV PHEV)] .) TCM (other than U0074:00) (See DTC TABLE ). Malfunction in wiring harness (including connector/terminal) between C-18 connector and ECM (See CIRCUIT INSPECTION .) (See CONNECTOR INSPECTION .) Malfunction in wiring harness (including connector/terminal) between C-68 connector and TCM (See CIRCUIT INSPECTION .) (See CONNECTOR INSPECTION .) Malfunction in wiring harness (including connector/terminal) between PCM and TCM (See CIRCUIT INSPECTION .) (See CONNECTOR INSPECTION .) Malfunction in wiring harness (including connector/terminal) between selector lever and TCM (See CIRCUIT INSPECTION .) (See CONNECTOR INSPECTION .) Malfunction in wiring harness (including connector/terminal) between backup power supply unit and TCM (See CIRCUIT INSPECTION .) (See CONNECTOR INSPECTION .) Malfunction in wiring harness (including connector/terminal) between drive motor control module and TCM (See CIRCUIT INSPECTION .) (See CONNECTOR INSPECTION .) Malfunction in wiring harness (including connector/terminal) between TCM and ECM (See CIRCUIT INSPECTION .) (See CONNECTOR INSPECTION .) (Refer to [HIGH VOLTAGE BATTERY REMOVAL/INSTALLATION ] in service information). Control valve body malfunction (TCM malfunction) (Refer to [CONTROL VALVE BODY REMOVAL/INSTALLATION ] in service information).
Repeatability verification procedure	Clear the DTC recorded in the memory. (See CLEARING DTC .) Perform the KOEO or KOER self test. (See DTC INSPECTION .)
Courtesy of MAZDA MOTORS CORP.
1	TCM
2	C-68 connector
3	C-18 connector
4	ECM
5	PCM
6	Selector lever
7	Backup power supply unit
8	Drive motor control module