2011 Mercedes ML-Class Owner's Manual - Page 188

186 Driving systems yellow segments showing operational readiness = light up. The selected transmission position determines which warning display is active when the engine is running. Transmission position D R or N P Warning display Front area activated Rear and front areas activated No areas activated Towing a trailer PARKTRONIC is deactivated for the rear area when you establish an electrical connection between your vehicle and a trailer. Driving and parking ! Fold in the ball coupling if the trailer tow hitch is not required. PARKTRONIC measures the minimum detection range to an obstacle from the bumper, not the ball coupling. ! Vehicles with an exterior spare wheel: Remove the detachable ball coupling if the trailer tow hitch is not required. PARKTRONIC measures the minimum detection range to an obstacle from the bumper, not the ball coupling. One or more segments light up as the vehicle approaches an obstacle, depending on the vehicle's distance from the obstacle. From the: Rsixth segment onwards, you will hear an intermittent warning tone for approximately two seconds. Rseventh segment onwards, you will hear a warning tone for approximately two seconds. This indicates that you have now reached the minimum distance. Deactivating/activating PARKTRONIC All models except ML 450 HYBRID (example) : To deactivate/activate PARKTRONIC ; Indicator lamp If indicator lamp ; lights up, PARKTRONIC is deactivated.