DTC U0074-00; Module Communication Between TCM And Pcm Error: Notes

DTC U0074:00	CAN communication: Module communication error (local CAN between TCM and PCM)
DETECTION CONDITION	Vehicle condition: TCM communication normal Status: Detects CAN BUS OFF malfunction Period: After CAN controller reset, confirmed by re -detection
FAIL-SAFE FUNCTION	Inhibits learning control. Inhibits direct mode. Inhibits AAS mode. Inhibits the TCC control and slip control. Inhibits 5GR and 6GR. Inhibits the neutral control. Inhibits the slope control.
POSSIBLE CAUSE	CAN bus communication line malfunction PCM malfunction TCM malfunction

Fig 1: TCM Circuit Diagram

Courtesy of MAZDA MOTORS CORP.