ESP: This is how the electronic stability program works in the car - AutoScout24

Functionality and importance of ESP in modern cars

The Electronic Stability Program, abbreviated ESP, is a computer-aided safety technology that falls under the category of assistance systems. According to the regulations of the European Union, since November 2014 only new vehicles can be registered if they have an ESP. This also applies to imported vehicles, where this stability control is usually referred to as ESC for Electronic Stability Control. As a result, the importance of ESP for safety while driving was raised to the same level as ABS, airbags or seat belts.

However, there is a serious difference to other security assistants. In modern vehicles, the ESP is automatically switched off by the system in certain situations, and in some models it can be deliberately deactivated by the driver. There are also exception rules for vehicles with a sports car character that are built in small numbers. The EU has exempted these cars from the obligation to install an ESP.

The sensory control of the ESP

The ESP works in a system network that also includes the anti-lock braking system (ABS) and the traction control system (TCS). ESP evaluates the data received from the sensors in order to make its own decisions. The ABS sensor data are preferably analyzed. But the safety system also relies on the TCS to detect subtle differences between the driver's control inputs and the vehicle's actual response.

The ESP constantly monitors the steering wheel angle in relation to the actual direction of travel and measures the speed of each wheel, the yaw angle and the steering angle up to 25 times per second. In this way, the ESP helps to compensate for driving errors that would otherwise impair the lateral dynamics. ABS and traction control do the same for longitudinal dynamics.

If the car loses lateral traction and starts to skid, either at the front or the rear, the ESP reacts. It alleviates the cause of the skid, if necessary it reduces the power on one wheel or the axle and if necessary individual brakes are applied. The ESP forces the car to follow the steering angle. In the event of understeer, the ESP brakes the rear wheel on the inside of the curve in order to steer the car more strongly. In the event of oversteer, ESP applies the brake on the outside front wheel to create a better pivot point and regain control of the rear of the car.

The ESP reacts when the car loses lateral traction and either the front or rear skids.

The tick on the control panel

As already explained, there are also new cars that are exempt from ESP. In addition, modern systems switch off the ESP in certain situations. In addition, there are models in which the driver can manually deactivate the electronic stability program. There are several reasons for this:

Differences between ESP and ESC

The ESP system, which most modern cars are equipped with, is produced by Bosch. Automakers fine-tune the default settings to best address the driving characteristics and sportiness of each vehicle. Many vehicle manufacturers have now developed their own ESP versions.