Audi A8 2019 Service Training page 43

Neutral idle control (NIC)
The neutral idle control system disengages the engine from
the transmission when stopping or when the vehicle is
stationary. Engine idle torque can be reduced to a minimum
because the engine does not have to counteract the con-
verter torque.
This helps save fuel and reduces C0
the engine runs more smoothly and quietly at low idle
torque. For this reason, the neutral idle control system is
activated as often as possible (see conditions for switching
on and off).
Switch-on conditions:
› Full adaption of the shift elements (brakes, clutches).
› ATF temperature > approximately 68 °F (20 C°)
› Gradient < 4% (the gradient is determined by the
1)
longitudinal acceleration sensor of the ABS system).
› Selector position D or R .
› Accelerator not pressed.
› Foot brake pressed.
Shut-off conditions:
› Selector position S or tiptronic mode.
2)
› Brake released.
(unless the vehicle is secured by the electro-mechanical
parking brake or hill start assist is active).
› Accelerator pressed.
› No ATF circulation by Transmission Fluid Auxiliary
Hydraulic Pump 1 V475 due to overload protection
function or fault.
› Towing mode detected.
The values given are intended as a guideline. They may deviate depending on the model version.
1)
Neutral idle control is not activated in selector position S in order to allow more direct acceleration. Without neutral control, clutch C or D is
2)
immediately closed when drive positions S1 and R are selected. This is why traction is noticeable on selection of 1st gear or R gear and like-
wise the traction reversal when shifting from 1st gear to R gear (or vice versa). This traction reversal is barely noticeable in selector position
D, because when neutral control is active clutch C or D is open and traction cannot be established until the brake has been released.
Reference
For more detailed information about the neutral idle control function in the 0D5 transmission, refer eSelf-Study Program
990163 The 2017 Audi Q7 Introduction.
emissions. In addition,
2
.
1)
Downhill assist
Downhill assist helps the driver to maintain a constant
speed on downhill gradients. In this case the transmission
selects the gear suitable for the gradient in order to main-
tain the speed selected at the time of braking via the engine
brake. Within the bounds of the system's physical limita-
tions it may be necessary to also correct the speed, if neces-
sary, using the brake pedal.
Downhill assist cuts out again as soon as the gradient
lessens or the accelerator pedal is pressed.
Depending on the gradient, downhill assist is active in
selector positions D and S while the brake is applied or
while cruise control is active.
Note:
Downhill assist cannot overcome the physical limitations of the
vehicle and therefore cannot maintain a set speed in all conditions.
The driver must always be ready to apply the brakes! Downhill
assist could also be inactive if the brakes were too hot as calculated
by the ABS control module.
Special features of the steering wheel tiptronic function
› After a long pull of the Tip- shift paddle (long pull-), the
transmission changes down into the lowest possible
gear.
› After a long pull of the Tip+ shift paddle (long pull +),
the transmission switches from temporary tiptronic
mode to automatic mode.
› In the event of a malfunction of the selector mechanism,
the positions P, R, N and D can be selected when the
vehicle is stopped and the brake is activated by simulta-
neously pressing both shift paddles(for longer than one
second).
› The "Tip-shifting in D/S" function, which allows gear-
shifts to be performed manually at any time, is available.
› The "Activation of coasting mode using Tip+" function
has been deactivated in order to simplify the function
assignments of the tiptronic steering wheel in the A8.
However, it is still possible to exit coasting mode by
pressing Tip-.
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