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1 Descent of noun
Hill Descent Control (HDC: Hill Descent Control) system, also known as a ramp control, which is an automatic control system for downhill driving, the driver You can not be in complete control of the brake pedal, by a smooth slope steep downgrade section. If necessary, the automatic control of each wheel braking device, in order to move slightly faster than the speed of forward travel, at this time the driver can fully concentrate on the control wheel. In short, in the case of the vehicles it can be controlled, through the steep road safety.
principles HDC system is a combination of engine braking cooperates with ABS anti-lock braking system, so the vehicle to maintain the steep slope down “low vehicle speed without loss of tire grip” in status. HDC required shift position in the transmission case 1 or the reverse gear (the steep slope forward and reverse downhill slope, two) when the action of the system will be substantially set vehicle speed limit, Land Rover cars to an example, provided HDC after the vehicle speed upper limit set at 9 km / h, so that the driver can control the vehicle comfortably.
steep slope system first seen on the 1997 Land Rover (Land Rover) published Freelander vehicles, then extended use on the same plant signboard cars Discovery; BMW worked behind the Land Rover club in between 1994 and 2000 and, therefore, the technology used in this HDC-based BMW X5 car body.