The automatic transmission control module (TCM) in the Mazda 3 is located in one of two places:
1. Inside the automatic transmission housing
* Remove the automatic transmission protective pan.
* The control box will be attached to the body on the left or right side.
2. In the engine compartment
*On some Mazda 3 models, the TCM is located in the engine compartment.
* It is located near the automatic transmission, usually attached to the firewall or under the hood.
Important:
*The exact location of the TCM may vary depending on the year, model and trim level of your Mazda 3.
* Access to the control unit may require removing some components or disconnecting electrical connectors.
* It is recommended that you consult your repair manual or consult a qualified mechanic to accurately locate the TCM in your specific vehicle.