Audi TT 2016 Introduction Manual page 31

Downhill assist
The downhill assist functions aids the driver on downhill
gradients. In selector lever positions "D" and "S", it is
activated when the brake pedal is depressed or when the
speed is set on the cruise control system. Downhill assist
tries to maintain the reduced speed within the bounds of
physical and drive limitations. The transmission selects a
gear appropriate to the gradient. It may be necessary to
additionally correct the vehicle's speed with the foot brake.
Launch control program
The launch control program enables maximum acceleration.
Conditions:
• The engine is at operating temperature.
• The wheels and the steering wheel are in the straight-
ahead position.
• The ESC-OFF button was briefly pressed once while the
engine was running.
• Selector lever is in the "S" position or in the tip-
tronic gate or dynamic mode is selected using
Audi drive select.
• Depress the brake pedal firmly for 1 second and hold it
down.
• Depress the accelerator pedal fully and hold it down.
• Ease off the brake.
Hill start assist systems
The hill start assist systems utilize the capabilities of the
ESC system and the parking brake. They assist the driver by
stopping the vehicle from inadvertently rolling away.
Hill start assist and integrated start assist are standard.
The requirements for system operation are that the driver's
door is closed, the driver's safety belt is fastened and the
engine is running.
Hill start assist is available when the brake pedal is
depressed and the vehicle is at a gradient of 5% or steeper.
When the vehicle stops on a gradient, the current brake
pressure is maintained by the ESC control valves. If the
brake pedal is released in order to drive away, brake pres-
sure is maintained for about 1.5 seconds. As soon as
enough drive torque is available to move the vehicle, the
brake is released.
This function aids starting on gradients because the vehicle
is largely prevented from rolling back. Hill start assist is
also available in reverse gear.
Given that downhill assist shifts down into no lower than
3rd gear, it is advisable to switch to tiptronic mode on very
steep gradients. This allows the vehicle to be shifted manu-
ally into 2nd or 1st gear to make use of the engine braking
effect and relieve the load on the brakes. Downhill assist
cuts out again as soon as the gradient lessens or the accel-
erator pedal is pressed.
When using the launch control program, the transmission
temperature will rise sharply. It is possible that the launch
control program will be unavailable until the transmission
has cooled sufficiently.
The launch control program puts maximum strain on parts
of the drivetrain, resulting in increased wear.
Integrated start assist is effective when the parking brake
is actuated. It is released at drive-away as soon as enough
drive torque is available to set the vehicle in motion. Inte-
grated start assist is only operational when the driver's
safety belt is fastened.
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