It is a system that accurately maintains the speed set by the driver without any external intervention. It automatically controls the speed of a car and only allows the vehicle to hit a speed set by the driver. It does not allow the car to cross that speed limit. This feature has become common among modern cars. You can even find this feature in the top-spec variants of some of the affordable hatchbacks and sedans.

How does the cruise control system work?

Cruise control in a car replicates the inputs of a driver to control the vehicle’s speed. But instead of pressing the accelerator pedal, it uses a different mechanism to maintain a constant cruising speed.

Initially, the system used a cable to control the accelerator (throttle valve). You can find these mechanisms in older cars. It adjusted the vehicle's speed by engaging the throttle with the help of an actuator that is controlled by a cable. The throttle valve is responsible for the power and speed generated by the engine. So, depending on the speed set by the driver, the system automatically adjusted the throttle position.

But with the advent of technology in the automotive industry, the cruise control system in modern cars entirely relies on electronics. Instead of a cable, the system now communicates with the throttle via various sensors connected to a computer (ECU - Electronic Control Unit). So, when you set a speed, the ECU calculates the throttle position and engages the throttle wirelessly.

The system constantly maintains the speed set by you (driver) irrespective of road conditions. For example, if there’s an incline ahead, cruise control adjusts the throttle accordingly to maintain the same speed.

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