Operating Cruise Control Systems in Cars

In modern designs, the cruise control may need to be turned on before use — in some designs it is always "on" but not always enabled, others have a separate "on/off" switch, while still others just have an "on" switch that must be pressed after the vehicle has been started. Most designs have buttons for "set", "resume", "accelerate", and "coast" functions. Some also have a "cancel" button. Alternatively, depressing the brake or clutch pedal will disable the system so the driver can change the speed without resistance from the system. The system is operated with controls easily within the driver's reach, usually with two or more buttons on the steering wheel spokes or on the edge of the hub like those on Honda vehicles, on the turn signal stalk like in many older General Motors vehicles or on a dedicated stalk like those found in, particularly Toyota and Lexus. Earlier designs used a dial to set speed choice.

The driver must bring the vehicle up to speed manually and use a button to set the cruise control to the current speed. The cruise control takes its speed signal from a rotating driveshaft, speedometer cable, wheel speed sensor from the engine's RPM or from internal speed pulses produced electronically by the vehicle. Most systems do not allow the use of the cruise control below a certain speed (normally around 25 mph/). The vehicle will maintain that speed by pulling the throttle cable with a solenoid, a vacuum driven servomechanism or by using the electronic systems built into the vehicle (fully electronic) if it uses a 'drive-by-wire' system.

All cruise control systems must be capable of being turned off both explicitly and automatically, when the driver depresses the brake and often also the clutch. Cruise control often includes a memory feature to resume the set speed after braking and a coast feature to disengage the system without braking. When the cruise control is engaged, the throttle can still be used to accelerate the car, but once the pedal