Stability System - Volvo XC90 Owner's Manual

Starting and driving

Stability system

When the stability system is in action, it may
seem like the car does not respond normally
to acceleration. This is because the system
detects the amount of friction on the road
surface and allows the different stability
system functions to operate.
The car is either equipped with STC (Stability
and Traction Control) - Stability and traction
control system or DSTC (Dynamic Stability
and Traction Control) - Dynamic stability and
traction control system.
Function/
STC
system
TC X
SC X
AYC
1. Option on certain markets.
Traction Control (TC)
The Traction Control function transfers
power from the spinning drive wheel to the
drive wheel which has grip by braking the
spinning drive wheel. To increase forward
traction in this situation, it may be necessary
to depress the accelerator more than usual. A
pulsing sound is heard when Traction Control
is working. This is completely normal. The TC
function is most active at low speeds. It
cannot be deactivated.
NNQ
Spin Control (SC)
The Stability Control function prevents the
drive wheels from slipping during acceler-
ation. This improves road safety on slippery
surfaces. Under certain conditions, such as
when driving with snow chains or in deep
snow or sand, it may be beneficial to
deactivate the SC function to increase
traction. This is done with the STC/DSTC
button.
Active Yaw Control (AYC)
The Active Yaw Control function automati-
1 cally brakes one or more wheels to stabilise
DSTC
the car in the event of a skid. If the brake
X
pedal were to be depressed in this situation,
X
it would feel more rigid than usual and a
X pulsing sound would be heard.
The AYC function is always active and cannot
be deactivated.
WARNING!
Suppressing the STC or DSTC system
may alter the driving characteristics of the
car. Always take care when cornering and
driving in slippery conditions.