Stability System - Volvo 2009 XC90 Owner's Manual

Dynamic Stability Traction Control
(DSTC)
The stability system consists of a number of
functions designed help reduce wheel spin,
counteract skidding, and to generally help
improve directional stability.
NOTE
A pulsating sound will be audible when the
system is actively operating and is normal.
Traction control (TC)
This function is designed to help reduce wheel
spin by transferring power from a drive wheel
that begins to lose traction to the wheel on the
opposite side of the vehicle (on the same axle).
TC is most active at low speeds.
This is one of DSTC's permanent functions and
cannot be switched off.
Spin control (SC)
The spin control function is designed to help
prevent the drive wheels from spinning while
the vehicle is accelerating.
Under certain circumstances, such as when
driving with snow chains, or driving in deep
snow or loose sand, it may be advisable to
temporarily switch off this function for maxi-
mum tractive force.
Controls on the left-side steering wheel lever
Temporarily switching off Spin control
1. Turn the thumbwheel (1) on the left-side
steering wheel lever until the
menu is displayed.
2. Hold down the RESET button (2) to toggle
between DSTC SPIN CONTROL ON
OFF .
06 Starting and driving
NOTE
•
The message
OFF
indicates that the stability sys-
tem's spin control function has tempo-
rarily been switched off.
•
The stability control indicator light will
illuminate and remain on until spin con-
trol has been reactivated.
•
The spin control function is automati-
cally enabled each time the engine is
started.
•
DSTC ON
functions are active.
Active Yaw Control (AYC)
DSTC
This function helps maintain directional stabil-
ity, for example when cornering, by braking
one or more of the wheels if the vehicle shows
or
a tendency to skid or slide laterally.
This is one of DSTC's permanent functions and
cannot be switched off.
WARNING
The car's handling and stability characteris-
tics will be altered if the DSTC system func-
tions have been disabled.

Stability system

DSTC SPIN CONTROL
indicates that all system
06
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