Trailer Stability Assist - Volvo XC90 Owner's Manual

STARTING AND DRIVING
|| When driving in hilly terrain and hot
climates
Under certain circumstances, there may be a risk
of overheating when towing a trailer. If the engine
and drive system overheats, a warning symbol
comes on in the driver display together with a
message.
The automatic gearbox selects the optimum gear
related to load and engine speed.
Steep inclines
Do not lock the automatic gearbox in a higher
gear than the engine "can cope with" - it is not
always a good idea to drive at a high gear with
low engine speed.
Parking on a hill
1. Depress the brake pedal fully.
2. Activate the parking brake.
3. Select gear position P.
4. Release the brake pedal.
Block the wheels with chocks when parking a car
with hitched trailer on a hill.
Starting on a hill
1. Depress the brake pedal fully.
2. Select gear position D.
3. Releasing the parking brake.
4. Release the brake pedal and start driving off.
14

Trailer Stability Assist

Electronic Stability Control
15
480
Related information
•
Trailer stability assist* (p. 480)
•
Checking trailer lamps (p. 481)
•
Towing capacity and towball load (p. 656)
•
Overheating in the engine and drive system
(p. 473)
•
Adverse driving conditions for engine oil
(p. 661)
Trailer stability assist*
The function of trailer stability assist (TSA
stabilise cars towing trailers in situations where
they begin snaking. The function is included in
15
the stability system ESC .
Reasons for snaking
The snaking phenomenon can occur with any
car/trailer combination. Snaking normally occurs
at high speeds. But, there is a risk of it occurring
at lower speeds if the trailer is overloaded or the
load is improperly distributed, 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 sur-
face 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.
Trailer stability assist function
The trailer stability assist function continually
monitors the car's movements, particularly lateral
14
) is to
* Option/accessory.