Electronic Throttle Control (ETC), sometimes called Drive-By-Wire (DBW), is a technology that replaces the conventional cable/linkage connection between a vehicle's accelerator pedal and the engine's throttle body. Almost all modern automobiles with mechanical linkage use a throttle position sensor to determine throttle plate opening once the linkage has set it. The most common arrangement is a bowden wire mechanism.
ETC, instead, determines necessary throttle opening using various input sensors (accelerator pedal position, engine RPM, engine vacuum (load), vehicle speed), and then positions the throttle via an actuator driven by a small, high-torque DC motor.
The main benefit of ETC is much quicker and accurate throttle control that helps the powertrain and emissions management systems deal with quickly changing conditions (ambient temperature, atmospheric pressure and accessory loads) that are normally outside the driver’s scope of control. In addition, this arrangement allows near seamless interaction between the motors, engines, controllers and drivelines of hybrid vehicles as well as motor/generators in electric vehicles (EV)s.