A special electrically-driven hydraulic pump and a high-pressure reservoir(or accumulator) provide "always-on" full brake pressure at each wheel. The computer-operated modulator valves control how much pressure actually operates the brakes at each wheel. In the new system, the bulky vacuum brake booster is now obsolete.
If the driver switches his foot quickly from accelerator to brake pedal, the electronic brake system recognizes the early signs of an emergency situation and reacts automatically. With the help of the high-pressure reservoir, the system raises the pressure in the brake connectors and instantaneously moves the pads onto the brake discs, which can then spring into action with full force as soon as the brake pedal is pressed. At highway speeds, this pre-loading of the braking system reduces stopping distance by about three percent.
In addition, the system automatically senses when the road is wet and imperceptibly applies the brakes just enough to keep the discs dry, so that brake operation remains fast and consistent in the rain.
FROM COUPE TO ROADSTER IN 16 SECONDS
At the push of a button, the new SL500's retractable hardtop can be fully opened or closed in just 16 seconds. (As a comparison, the Mercedes-Benz SLK-Class' retracting roof takes about 25 seconds.)
As the power roof retracts, the rear window glass also rotates so that its curvature nestles inside the stowed roof panel, providing a surprisingly large cargo area of 6.8 cubic feet. With the top up, the trunk holds 9.7 cubic feet — over 1.8 more than its predecessor.