Electronic Stability Control

Electronic Stability Control (ESC) is the generic term for systems designed to improve a vehicle's handling, particularly at the limits where the driver might lose control of the vehicle. Robert Bosch and Mercedes Benz co-developed the first ESC system called Electronic Stability Program (ESP) that was used by Mercedes-Benz in their flagship S-Class. Mercedes Benz licensed this for use to other car manufacturers at no cost, including BMW with their 7 Series in 1995. Mercedes-Benz became the first manufacturer to make ESC standard across its model range in 1999, with BMW following suit in 2000.

ESC was introduced to the mass market by Mercedes-Benz/Bosch, Continental Automotive Systems, Delphi and TRW, usually under the broader name of Electronic Stability Control, which is the more common term recognized by the Society of Automotive Engineers, although individual car manufacturers use a range of different marketing names.

ESC compares the driver's intended direction in steering and braking inputs, to the vehicle's response, via lateral acceleration, rotation and individual wheel speeds. ESC then brakes individual front or rear wheels and/or reduces excess engine power as needed to help correct understeer or oversteer. ESC also integrates all-speed traction control, which senses drive-wheel slip under acceleration and individually brakes the slipping wheel or wheels, and/or reduces excess engine power, until control is regained. ESC cannot override a car's physical limits. If a driver pushes the possibilities of the car's chassis and ESC too far, ESC cannot prevent a crash. It is a tool to help the driver maintain control.