Honda Ridgeline 2006-2008
This vehicle uses an Antilock Brake System (ABS). If the Antilock Brake Module (ABM) senses impending rear wheel lock-up, it will energize the isolation solenoid. This prevents a further increase of driver induced brake pressure to the rear wheels. If this initial action is not enough to prevent rear wheel lock-up, the ABM will momentarily energize a dump solenoid. This opens the dump valve to vent a small amount of isolated rear brake pressure to an accumulator. The action of fluid moving to the accumulator reduces the isolated brake pressure at the wheel cylinders. The dump (pressure venting) cycle is limited to very short time periods (milliseconds). The ABM will pulse the dump valve until rear wheel deceleration reaches the desired slip rate programmed into the ABM. The system will switch to normal braking once wheel locking tendencies are no longer present.
As part of the anti-lock brake system, this vehicle is equipped with Vehicle Stability Assistance (VSA). VSA is a computerized technology that improves the safety of a vehicle's handling by detecting and preventing skids. When VSA detects loss of steering control, VSA automatically applies individual brakes to help "steer" the vehicle where the driver wants to go. Braking is automatically applied to individual wheels, such as the outer front wheel to counter oversteer, or the inner rear wheel to counter under steer. Some VSA systems also reduce engine power until control is regained.
VSA compares the driver's intended direction (by measuring steering angle) to the vehicle's actual direction (by measuring lateral acceleration, vehicle rotation (yaw) and individual road wheel speeds). If the vehicle is not going where the driver is steering, VSA then brakes individual front or rear wheels and/or reduces excess engine power as needed to help correct under steer (plowing) or oversteer (fishtailing).
VSA incorporates yaw rate control into the anti-lock braking system (ABS). Yaw is rotation around the vertical axis; i.e. spinning left or right. Anti-lock brakes enable VSA to brake individual wheels. The VSA used on this vehicle also incorporates a Traction Control System (TCS), 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.