The ESC is the acronym for Electronic Stability control. The ESC is a braking system that combines the functions of a brake servo unit and the ABS (Antilock Braking System) equipment including ESP (Electronic Stability Program). The ESC is a technology that improves the safety of a vehicle's stability by detecting and reducing loss of traction. When ESC detects loss of a steering control, it automatically applies the brakes to help steer the vehicle where the driver intends to go. Braking is automatically applied to wheels individually. Brake switch is mounted on the brake pedal assembly and is used to send the status of the brake pedal to the HECU. There are two separate switches in the switch housing. The Brake Switch is normally closed while the Brake Light Switch is normally open.