Volvo S90 2020 Owner's Manual page 491

Hide thumbs Also See for S90 2020:
Table of Contents

Advertisement

Trailer stability assist*
The function of trailer stability assist (TSA
which is included in the stability system
32
ESC
, is to stabilise cars towing trailers in
situations where they begin snaking. The
function is available with towbar installation,
contact a Volvo dealer for more information.
Reasons for snaking
The snaking phenomenon can occur with any
car/trailer combination. Snaking normally
occurs at high speeds. However, there is a risk
of it occurring at lower speeds if the trailer is
overloaded or the load is improperly distrib-
uted, e.g. too far back.
In order for snaking to occur, there must be a
triggering factor, e.g.:
Car with trailer subjected to a sudden and
powerful side wind.
Car with trailer drives on an uneven road
surface or in a pothole.
Sweeping steering wheel movements.
If snaking has started, it could be difficult or
even impossible to suppress. This makes the
car/trailer combination difficult to control and
there is a risk that you could, for example, end
up in the wrong lane or leave the carriageway.
31
Trailer Stability Assist
32
Electronic Stability Control
Trailer stability assist function
The trailer stability assist function continually
31
),
monitors the car's movements, particularly lat-
eral movements. If snaking is detected, the
front wheels are individually braked. This
serves to stabilise the car/trailer combination.
This is often enough to help the driver regain
control of the car.
If snaking is not eliminated the first time that
trailer stability assist intervenes, the car/trailer
combination is braked with all wheels and
engine power is reduced. Once snaking has
been gradually suppressed and the car/trailer
combination is stable once again, the system
stops regulating and the driver once again has
full control of the car.
NOTE
The stability function is deactivated if the
driver chooses to activate
Mode
via the menu system in the centre
display.
Trailer stability assist may fail to intervene if
the driver uses severe steering wheel move-
ments to try to rectify the snaking because in
such a situation the system cannot determine
whether it is the trailer or the driver causing
the snaking.
NOTE
Retrofitting a towbar requires an update of
the car's software, contact a Volvo dealer.
Related information
Driving with a trailer (p. 487)
Electronic stability control (p. 291)
ESC Sport
STARTING AND DRIVING
When Trailer Stability Assist
(TSA) is operating, the ESC
symbol flashes in the driver
display.
* Option/accessory.
489

Advertisement

Table of Contents
loading

Table of Contents