What does it mean when the EPS light comes on in a car?

[LeOlivia]

When the EPS light comes on in a car, it indicates a fault in the Electric Power Steering system. The function of EPS is to use the power generated by an electric motor to assist the driver with steering, providing direct steering assistance through the electric power motor. This eliminates the need for components such as the power steering oil pump, hoses, hydraulic fluid, drive belt, and pulley mounted on the engine found in hydraulic power steering systems, saving energy and protecting the environment. The working principle of EPS is: when the steering wheel is operated, the torque sensor mounted on the steering column continuously measures torque and steering angle signals. These signals, along with the vehicle speed, are input into the Electronic Control Unit (ECU). After calculation and processing by the ECU, it controls the motor to output a corresponding torque signal in terms of magnitude and direction. The main torque from the motor is then increased through a speed reducer and applied to the steering system to achieve power steering assistance for the vehicle.