Seat Leon 2010 Owner's Manual page 188

186 Intelligent technology
Electronic Stability Programme (ESP)*
ESP reduces the danger of skidding by braking the wheels individually.
The system uses the steering wheel angle and road speed to calculate the
changes of direction desired by the driver, and constantly compares them
with the actual behaviour of the vehicle. If the desired course is not being
maintained (for instance, if the car is starting to skid), then the ESP compen-
sates automatically by braking the appropriate wheel.
The forces acting on the braked wheel bring the vehicle back to a stable
condition. If the vehicle tends to oversteer, the system will act on the front
wheel on the outside of the turn.
Steering manoeuvre recommendations
This is a complementary safety function included in the ESP This function aids
the driver to better stabilize the vehicle in a critical situation. For example, in
case of sudden braking surface with varied adherence, the vehicle will tend
to destabilise its trajectory to the right or to the left. In this case the ESP
recognizes the situation and helps the driver with a counter steering
manoeuvre from the power steering.
This function simply provides the driver with a recommended manoeuvre in
critical situations.
The vehicle does not steer itself with this function, the driver has full control
of the vehicle at all times.
WARNING
•
It must be remembered that ESP cannot defy the laws of physics. This
should be kept in mind, particularly on slippery and wet roads and when
towing a trailer.
•
Always adapt your driving style to suit the condition of the roads and
the traffic situation. Do not let the extra safety afforded by ESP tempt you
into taking any risks when driving, this can cause accidents.
Caution
•
In order to ensure that ESP functions correctly, all four wheels must be
fitted with the same tyres. Any differences in the rolling radius of the tyres can
cause the system to reduce engine power when this is not desired.
•
Modifications to the vehicle (e.g. to the engine, the brake system, running
gear or any components affecting the wheels and tyres) could affect the effi-
ciency of the ABS, EDL, ESP and TCS.
Anti-lock brake system (ABS)
The anti-lock brake system prevents the wheels locking during braking
⇒ page 184.
Electronic differential lock (EDL)*
The electronic differential lock helps prevent the loss of trac-
tion caused if one of the driven wheels starts spinning.
EDL helps the vehicle to start moving, accelerate and climb a gradient in slip-
pery conditions where this may otherwise be difficult or even impossible.
The system will control the revolutions of the drive wheels using the ABS
sensors (in case of an EDL fault the warning lamp for ABS lights up)
⇒ page 81.
At speeds of up to approximately 80 km/h, it is able to balance out differ-
ences in the speed of the driven wheels of approximately 100 rpm caused by
a slippery road surface on one side of the vehicle. It does this by braking the
wheel which has lost traction and distributing more driving force to the other
driven wheel via the differential.