3 Series E91 335i (N54) TOUR
Active Cruise Control differentiates between 2 driving conditions:
•
Cruise control with specified set speed
A selected set speed (in the range 30 km/h - 180 km/h) is automatically maintained on open roads
without vehicles driving ahead.
•
Cruise control with speed adapted to that of vehicle driving ahead
If a slower vehicle is detected on the vehicle's own track, the vehicle's own speed will be adapted to that of
the vehicle driving ahead
At the same time, a distance from this vehicle preset by the driver is established (4 fixed timed separations
can be selected).
The timed separation from a vehicle driving ahead is no less than 1 second under stationary conditions. In
certain conditions (e.g. when a vehicle cuts in a short distance ahead), this timed separation may briefly be
less than 1 second.
Lens heating
The lens of the ACC sensor is made of plastic. The built-in lens heating ensures better availability of Active
Cruise Control in winter weather conditions.
The lens heating is activated by the ACC sensor. The heating is controlled via a pulse-width modulated signal
(PWM signal). The heating coil is integrated into the lens of the ACC sensor
The lens heating is only activated within a certain ambient temperature range (approx. +5
°
C to -5
°
C).
Reason: Only at temperatures around zero is snow wet or moist. At temperatures well below this, snow will be
dry. To prevent snow from thawing on the lens and creating an artificial coating, the heating is switched off below
a certain ambient temperature. The current ambient temperature value is transmitted by the instrument cluster.
•
Conditions required for switch-on
-
Engine ON
-
ACC ON
-
Ambient temperature between -5
°
C and +5
°
C
•
Safety cutout
-
Temperature in ACC sensor over 50
°
C
(measured by interior temperature sensor in ACC sensor control unit)
-
Voltage greater than 16 volts
The safety cutout shuts down the lens heating. Active Cruise Control remains activated. (No fault memory
entry)
•
Monitoring
The lens heating is monitored for open and short circuits in the heating coil.
If the monitoring reports a fault, Active Cruise Control will be shut down. (Fault memory entry)
Low-voltage cutout and high-voltage protection for ACC sensor
The ACC sensor works with a supply voltage of 9 to 16 volts.
•
Low-voltage cutout
If the on-board supply voltage drops below about 9 volts, the ACC sensor will perform a low-voltage cutout
and a fault memory entry will be stored.
The ACC sensor will be reactivated when the on-board supply voltage exceeds 9.8 volts again.
•
Overvoltage protection
If the on-board supply voltage exceeds about 17.5 volts, the ACC sensor will perform a cutout with a fault
SBT Cruise control E90, E91, E92, E93
BMW AG - TIS
24.02.2013 03:40
Issue status (12/2007) Valid only until next DVD is issued
Copyright
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