188 DRIVING AND OPERATINGsupplement the power brake systemunder conditions where the driver hasquickly and forcefully applied thebrake pedal in an attempt to quicklystop or slow down the vehicle. Thestability system hydraulic brakecontrol module increases brakepressure at each corner of the vehicleuntil the ABS activates. Minor brakepedal pulsation or pedal movementduring this time is normal and thedriver should continue to apply thebrake pedal as the driving situationdictates. The brake assist feature willautomatically disengage when thebrake pedal is released or brake pedalpressure is quickly decreased.Hill Start Assist (HSA)This vehicle has a Hill Start Assist(HSA) feature, which may be usefulwhen the vehicle is stopped on agrade sufficient enough to activateHSA. This feature is designed toprevent the vehicle from rolling, eitherforward or rearward, during vehicledrive off. After the driver completelystops and holds the vehicle in acomplete standstill on a grade, HSAwill be automatically activated. Duringthe transition period between whenthe driver releases the brake pedal andstarts to accelerate to drive off on agrade, HSA holds the braking pressurefor a maximum of two seconds toensure that there is no rolling. Thebrakes will automatically release whenthe accelerator pedal is applied withinthe two-second window. It will notactivate if the vehicle is in a drive gearand facing downhill, or if the vehicleis facing uphill and in R (Reverse).Ride Control SystemsTraction Control/ElectronicStability ControlSystem OperationThe vehicle has a Traction ControlSystem (TCS) and StabiliTrak ® , anelectronic stability control system.These systems help limit wheel slipand assist the driver in maintainingcontrol, especially on slippery roadconditions.TCS activates if it senses that any ofthe drive wheels are spinning orbeginning to lose traction. On anAll-Wheel-Drive (AWD) vehicle, thesystem will operate if it senses thatany of the wheels are spinning orbeginning to lose traction. When thishappens, TCS applies the brakes to thespinning wheels and reduces enginepower to limit wheel spin.StabiliTrak activates when the systemsenses a discrepancy between theintended path and the direction thevehicle is actually traveling.StabiliTrak selectively applies braking
