Final answer:
Technician B is correct. All vehicles use an alternator as the charging unit.
Step-by-step explanation:
Technician A says that many vehicles use an AC generator as the charging unit. Technician B says that all vehicles use an alternator as the charging unit. Who is correct?
Technician B is correct. All vehicles use an alternator as the charging unit, not an AC generator. An alternator is a type of AC generator that converts mechanical energy from the engine into electrical energy to charge the battery and power the electrical systems of the vehicle.