DSR is an aid to assist you when driving downhill. It keeps the speed of travel at the speed selected on the on-board computer.

The steeper the downhill gradient, the greater the DSR braking effect on the vehicle. When driving on flat stretches of road or on an uphill gradient, the DSR braking effect is minimal or non-existent.

The set speed is set to 4 mph (6 km/h) at the factory; this can be adjusted using the onboard computer.

WARNING  
Downhill Speed Regulation (DSR) is a convenience system designed to assist the driver during vehicle operation. The system setting must be appropriate to the topographical and weather conditions encountered, which can change quickly. The driver is responsible for the vehicle speed and for safe brake operation at all times.
Depending on the programmed speed, actual vehicle speed and gradient, switching on DSR while driving can cause the vehicle to slow down rapidly, and you may hear a sound, caused by the activation of the vehicle's brake system through DSR. Sudden and unexpected deceleration can result in loss of vehicle control, causing an accident and/or serious personal injury to you and others. Do not switch on DSR in a situation where rapid deceleration could result in a loss of vehicle control.

DSR controls the set speed when it is active and the automatic transmission is in the D, R or N position. You can drive at a higher or a lower speed than that set on the on-board computer at any time by accelerating or braking.

WARNING  
If you depress the accelerator pedal with DSR activated, the vehicle can drive faster than the programmed set speed. You should therefore drive downhill with particular caution as it could lead to an accident and/or serious injury to you or others. Keep in mind that as soon as you remove your foot from the accelerator pedal with DSR switched on, DSR will start regulating the vehicle's speed including use of brakes if required. Depending on the programmed set speed, actual vehicle speed and gradient, DSR can cause the vehicle to slow down rapidly. Sudden and unexpected deceleration can result in loss of vehicle control, causing an accident and/or serious personal injury to you and others.

For information about driving off-road, see.