Pre Sense Rear - Audi Q7 2017 Manual

Pre sense rear

With Audi pre sense rear, the following actions can be
initiated:
• RECAS warning (Rear End Collision Avoidance System).
• Inflation of the side bolsters in the seats and seat backs.
• Closing the panoramic glass sunroof.
• Closing of the side windows.
• Speed-dependent partial or full tensioning of the electri-
cally reversible safety belt tensioners.
Audi pre-sense basic is always installed in combination with
Audi pre-sense rear. Audi pre-sense rear is only possible if
the vehicle has Audi side assist.
Two "mid-range" radar sensors are able to detect objects
within a range of approximately 76.5 yards (70 meters)
behind the vehicle. Lane Change Assistance Control Module
J769 and Lane Change Assistance Control Module 2 J770
are mounted behind the rear bumper cover. Each module is
combined with a radar sensor to form a unit. They commu-
nicate via a sub-bus system. In addition, J769 (master
module) is connected to the Extended CAN.
Function
The radar sensors continuously monitor the traffic follow-
ing the vehicle whenever Audi side assist is inactive. Control
modules J769 and J770 evaluate and condition the signals
they receive and determine the distance to following vehi-
cles within their detection range.
Based on the information supplied by ABS Control Module
J104, the vehicle knows its own speed. The Audi side assist
control modules J770 and J769 compute the speeds of the
following vehicles based on this information. The following
information is available to Audi pre sense rear
• Distance to following vehicles.
• Speed of following vehicles.
• Speed of own vehicle.
3) The following vehicles must be within the detection range of the radar sensors.
Installation location
J769 is installed in the rear bumper on the right-hand side
of the vehicle. 2 J770 is installed in the rear bumper on the
left-hand side of the vehicle.
Lane Change Assistance
Control Module 2 J770
If an Audi side assist control module detects a critical
pre-sense rear situation, J769 sends the information to the
Gateway. A critical situation is defined as one in which a
following vehicle would collide with one's own vehicle
unless further action is taken by the driver of the following
vehicle.
J533 forwards these signals to Airbag Control Module J234.
J234 in turn decides on the basis of the information which
actuators to activate and distributes the information to the
different control modules.
:
3)
Lane Change Assistance
Control Module J769
(master control unit)
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