System Operation: Arm
WARNING: This page is about a different car, the 2010 Land Rover Range Rover Sport. However, it is still accessible from the selected car via links, so may be relevant.
The ARM function uses the brakes and the engine to attempt to restore stability if the vehicle is forced into such a harsh maneuver that it risks tipping over.
The ABS module monitors driver inputs and vehicle behavior using various powertrain signals and the inputs from the wheel speed sensors, the steering angle sensor and the yaw rate and lateral acceleration sensor. These are compared with modeled behavior and, if vehicle behavior reaches a given risk level, the ABS module cuts the engine power, or brakes one or more wheels, just enough to help the vehicle regain its poise and help the driver remain in control.
While the ignition is on, ARM is permanently enabled, even when DSC has been selected off.