Audi Q7 e-tron quattro 4M - Page 49

49
Neutral idle control (starting with and without neutral idle control)
If the internal combustion engine is in operation, the internal
combustion engine and the gearbox are disconnected by the
neutral idle control system when the vehicle is at a standstill.
As a result, the driveline is isolated acoustically and vehicle noise is
reduced. The torque load for the internal combustion engine is also
reduced, as the engine no longer has to counteract the usual
converter torque produced by a torque converter automatic
gearbox.
Neutral idle control in 1st gear
As soon as the vehicle is ready for operation (refer to page 39 of
SSP650) and the ATF pressure supply is available (refer to
page42), brake A is closed and brake B is applied (kisspoint). The
neutral idle control system is still not active (selector position P or
N) at this point.
The neutral idle control system is active if the applicable conditions
are met, the driver has applied the brake and selector position D is
selected. If selector position D is selected, clutch C of 1stgear is
not initially closed.
As soon as the driver has released the brake, brake B and clutch C
are closed. Brake B, which is already at the kisspoint, is closed with
a steep rise in pressure, while clutch C is closed with a gentle rise
in pressure. Traction can be comfortably established in this way.
The remainder of the start-up operation is performed using the
torque converter.
Neutral idle control when start-stop mode is active
If the internal combustion engine is shut o as a result of start-
stop mode and then the instruction to restart is issued, the neutral
idle control system is reactivated when selector position D is
engaged. To speed up ATF pressure buildup, the auxiliary hydraulic
pump 1 for gear oil V475 assists the closing of brake A and the
application of brake B.
The rest of the sequence follows the neutral idle control function
described above.
Stopping with the neutral idle control system
The neutral idle control function, which is used exclusively by the
AudiQ7(type4M) with internal combustion engine, is not avail-
able for the AudiQ7e-tronquattro.
Conditions which allow neutral idle control to be activated
• The internal combustion engine is in operation.
• Full adaption of the shift elements (brakes, clutches)
• ATF temperature >approx. 20°C
1)
• Road gradient <4%
1)
(the gradient is determined by the
longitudinal acceleration sensor of the brake electronics.)
• Selector positionD engaged
• Accelerator not pressed
• Foot brake pressed
Switch-o conditions
• Selector positionS
2)
, R
3)
or tiptronicmode selected
• Brake released
(unless the vehicle is secured by the electro-mechanical
parking brake or hill start assist is active.)
• Accelerator pressed
Shift matrix
The shift matrix illustrates, in excerpts, the activation of the shift
elements for 1st gear. For more information about the shift matrix
of the 0D7 gearbox, refer to page 46.
Brake closed
Brake at kisspoint
Open/closed dep. on clutch status
The neutral idle control system can be activated or deactivated
with the diagnostic tester by selective adaptation (refer to
page64).
1)
The given values provide a guideline and are not binding. They may deviate depending on model version.
2)
In selector positionS neutral idle control is not activated in order to allow more direct drive-away. Without neutral idle control, clutch C is immediately closed
if selector position S is selected. This is why it is possible to notice traction after selecting 1st gearand traction reversal after shifting from 1stgearto R
gear(or vice versa). Traction is barely noticeable after selecting 1st gear in selector position D, because clutch C is open when neutral idle control is active and
traction cannot be established until the brake has been released.
3)
Unlike the AudiQ7 (type4M) powered exclusively by the internal combustion engine, neutral idle control is not implemented in R gear.
649_090
1st gear
Shift matrix
ProCarManuals.com
< Back
Forward >
Ξ Contents