DTC U0074-00: Can System Communication Error (Local Can Between TCM And Pcm): Notes

WARNING: This page is about a different car, the 2016 Mazda CX-5. However, it is still accessible from the selected car via links, so may be relevant.

DTC U0074:00	CAN system communication error (local CAN between TCM and PCM)
DETECTION CONDITION	Under the following condition, a communication error (local CAN between TCM and PCM) occurs: Battery voltage is 10 V or more .
FAIL-SAFE FUNCTION	Set to TCC control. Inhibits learning control. Inhibits manual mode. Inhibits neutral idle control. Inhibits AAS. Inhibits 5GR and 6GR. Inhibits shift down when the accelerator pedal is depressed.
POSSIBLE CAUSE	CAN communication line malfunction between TCM and PCM (local CAN between TCM and PCM) PCM DTC is stored. TCM malfunction
SYSTEM WIRING DIAGRAM	Not applicable