Stability System - Volvo 2009 S40 Owner's Manual

Stability Traction Control (STC)/
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.
A pulsating sound will be audible when the
system is actively operating and is normal.
Function/ STC
system
TC X
SC X
AYC
A Option on certain models.
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 the stability system's permanent
functions and cannot be switched off.
1 Models equipped with All Wheel Drive (AWD) have an integrated traction control function that cannot be disabled. DSTC is optional on AWD models.
A
DSTC
X
A - thumb wheel, B - RESET button
X
Spin control (SC)
X 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
1
.
06 Starting and driving

Stability system

Temporarily switching off Spin control
1. Turn the thumbwheel (A) on the left-side
steering wheel lever until the
menu is displayed.
2. Hold down the RESET button (B) to toggle
STC/DSTC SPIN CONTROL
between
ON or OFF .
NOTE
•
The message STC/DSTC SPIN
CONTROL OFF
indicates that the sta-
bility system's spin control function has
temporarily been switched off.
•
The stability control indicator light
will illuminate and remain on until spin
control has been reactivated.
•
The spin control function is automati-
cally enabled each time the engine is
started.
•
STC/DSTC ON indicates that all sys-
tem functions are active.
Active yaw control – AYC (DSTC only)
This function helps maintain directional stabil-
ity, for example when cornering, by braking
one or more of the wheels if the vehicle shows
a tendency to skid or slide laterally.
STC/DSTC
06
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