Variable Effort Steering Description

The variable effort steering (VES) system varies the driver effort that is required to steer as the vehicle speed changes. At low speeds, the system provides maximum power assist for easy turning and parking maneuvers. At higher speeds, steering effort is increased in order to provide the driver with firmer steering (road feel) and directional stability.

The VES system varies the driver effort by reducing the current to the variable effort steering (VES) actuator on the power steering gear. When the vehicle is stationary, the system provides maximum current, allowing maximum power steering assist. As the vehicle speed increases, the current is decreased, reducing the amount of steering assist. The VES system consists of the following power steering components:

• The speed sensitive power steering (SSPS) control module
• The variable effort steering (VES) actuator
• The power rack and pinion
• The power steering pump