Alternator Control Module ACM (4/98, 6/26) [2019-2021, B4204T23; B4204T27]: Description

The alternator control module ACM regulates the alternator. The alternator control module ACM regulates the alternator by directing current to the excitation rotor windings. The alternator spins with the motor and only produces current when the windings are flowing with current and creating a magnetic field.