Learn the top signs of a faulty Transmission Control Module (TCM) and its replacement cost. Keep your car running smoothly with our expert advice.

Transmission Control Module (TCM) faults are not unknown on these early Mazda 3s. Symptoms usually involve erratic shifting, a failure to select gear at all and having the car go into limp-home mode.

The transmission’s computer, the transmission control module (TCM), takes all of this into account to strategize the ideal shift and clutch pressure, so if any one input is missing, it won’t ...

The power control module, aka PCM, manages the engine, transmission and other systems based on information it receives from various sensors around the vehicle.