If it has one, it'll be located somewhere in the engine compartment. You want anything more specific, you need to give a model.
Dodge ECM's are normally located in or acting as the air intake box bolted to the left inner fender.
Where is coil located on a 1989 dodge dynasty at
Were is the ecm located on a 2001 dakota
Next to the battery.
Passenger side of the firewall.
The regulator in my 90 ram van is in the ECM or ECU
the ECM is located under the hood on the driver side fender it is in a black box i just replaced it
The ECM (computer) is located on the passenger side kick panel!
Under the hood, on the passenger side firewall.
under the coil packs which are located at the rear of the motor on top
behind the glove box or kick panel on passenger side
It is is located on the right side (sitting in vehicle) of and bolted to the firewall.