Driver Alert System - Dac - Volvo V70 Owner's Manual

04 Comfort and driving pleasure
Driver Alert System – DAC*
Introduction
The Driver Alert System is intended to assist
drivers whose driving ability is deteriorating or
who are inadvertently leaving the lane they are
driving on.
The Driver Alert System consists of two differ-
ent functions, which can either be switched on
at the same time or individually:
•
Driver Alert Control (DAC)
•
Lane Departure Warning (LDW), see
04
page 175.
A switched-on function is set in standby mode
and is not activated automatically until speed
exceeds 65 km/h.
The function is deactivated again when speed
decreases to below 60 km/h.
Both functions use a camera which is depend-
ent on the lane having side markings painted
on each side.
WARNING
The Driver Alert System does not work in all
situations but is instead only intended to be
of supplementary assistance.
The driver always has ultimate responsibility
that the car is driven safely.
*
172
Option/accessory, for more information, see Introduction.
General information on Driver Alert
Control - DAC
The function is intended to attract the driver's
attention when he/she starts to drive less con-
sistently, e.g. if he/she becomes distracted or
starts to fall asleep.
A camera detects the side markings painted on
the carriageway and compares the section of
the road with the driver's steering wheel move-
ments. The driver is alerted if the vehicle does
not follow the carriageway evenly.
NOTE
The camera sensor has certain limitations,
see page 169.
The objective for DAC is to detect slowly dete-
riorating driving ability and it is primarily
intended for major roads. The function is not
intended for city traffic.
In some cases driving ability is not affected
despite driver fatigue. In which case there may
not be any warning issued for the driver. For
this reason it is always important to stop and
take a break in the event of any signs of driver
fatigue, irrespective of whether or not DAC
issues a warning.
NOTE
The function must not be used to extend a
driving stint. Always plan breaks at regular
intervals and ensure that you are fully
rested.
Limitation
In some cases the system may issue a warning
despite driving ability not deteriorating, for
example:
•
if the driver tests the LDW function.
•
in strong side winds.
•
on rutted road surfaces.