Volvo XC40 2019 Owner's Manual page 408

STARTING AND DRIVING
||
Related information
Trailer Stability Assist* (p. 406)
•
Checking trailer lights (p. 407)
•
Towing capacity and tongue weight
•
(p. 600)
Overheating of engine and transmission
•
(p. 399)
18 Trailer Stability Assist
19 Electronic Stability Control
406
Trailer Stability Assist*
Trailer Stability Assist (TSA 18 ) is a function
designed to help stabilize a vehicle that is
towing a trailer when the vehicle and trailer
have begun to sway. The function is part of
the Electronic Stability Control system ESC
Reasons for swaying
A vehicle towing a trailer may begin to sway
for various reasons. Normally this only occurs
at high speeds. However, if the trailer is over-
loaded or unevenly distributed, e.g. too far
back, there is a risk of swaying even at low
speeds.
Swaying may be caused by factors such as:
The vehicle and trailer are hit by a sudden,
•
strong crosswind.
The vehicle and trailer are traveling on an
•
uneven road or over a bump.
Sudden movements of the steering wheel.
•
Once swaying has begun, it can be difficult or
impossible to stop it. This makes the vehicle
and trailer difficult to control and there is a risk
of swerving into oncoming traffic or driving off
the road.
Trailer Stability Assist function
Trailer Stability Assist continuously monitors
the vehicle's movements, particularly lateral
movements. If swaying is detected, the brakes
are applied individually on the front wheels,
which has a stabilizing effect on the vehicle
and trailer. This is often enough to enable the
driver to regain control of the vehicle.
19 .
If the Trailer Stability Assist function's first
attempt is not adequate to stop the swaying
motion, the brakes are applied on all wheels
and engine power is temporarily reduced. As
the swaying motion begins to decrease and
the vehicle and trailer have once again
become stable, TSA stops regulating the
brakes/engine power and the driver regains
control of the vehicle.
NOTE
Trailer Stability Assist is deactivated if the
driver selects the sport mode by deactivat-
ing ESC in the center display's menu sys-
tem.
Trailer Stability Assist may not intervene if the
driver tries to compensate for the swaying
motion by moving the steering wheel rapidly,
because the system will then not be able to
determine if it is the trailer or the driver caus-
ing the swaying.
* Option/accessory.