DTC P1738-00: Automatic Transaxle Internal Malfunction (TCM) (Us): Outline

WARNING: This page is about a different car, the 2020 Mazda CX-30. However, it is still accessible from the selected car via links, so may be relevant.

DTC P1738:00 (TCM, EV6A-EL, EV6AX-EL, US) DETECTION CONDITION AND POSSIBLE CAUSE

System malfunction location	Automatic transaxle internal malfunction
Detection condition	Malfunction location cannot be determined based on combination of gear ratio malfunction and oil pressure switch pattern malfunction.
Fail-safe	Inhibits learning control. Inhibits manual mode. Inhibits neutral idle control. Inhibits AAS.
Possible cause	ATF is less than specified value Automatic transaxle internal malfunction
System wiring diagram	Not applicable
Connector diagram	Not applicable