2020 Seat Leon Owner's manual

Checking and refilling levels
by duly qualified and trained technical
st aff .
T
ake care when handling flammable sub-
stances.
In addition to a 12-volt battery, the vehicle
may be fitted with a 48-volt battery located
underneath the front passenger seat.
The works that are to be carried out on the
48 volt battery should be performed exclu-
sively by a specialised workshop with duly
qualified technical staff, trained according to
the SEAT guidelines.
Overview of the 48 volt system
The 48 volt system consists of the following
components, among others:

Practical tips
Energy management Optimisation of the st ar
ting ca-
pacity The power management controls the distri-
bution of el
ectrical ener

gy and thus helps to
ensure that there is always enough power
available to start the engine.
If a vehicle with a conventional electrical sys-
tem is left parked for a long time, the battery
will gradually lose its charge because certain
electrical devices, such as the electronic
gearbox lock continues to draw current even
when the ignition is off. In some cases there
may not be enough power available to start
the engine.
Your vehicle is equipped with an intelligent
power management system to control the
distribution of electrical energy. This signifi-
cantly improves reliability when starting the
engine, and also prolongs the useful life of the
battery.
The main functions incorporated in the power
management system are battery diagnosis,
residual current management and dynam-
ic power management.
Battery diagnosis
The battery diagnosis function constantly
registers the condition of the battery. Sensors detect the battery voltage, battery current
and batt
ery t

emperature. This enables the
system to calculate the current power level
and charge condition of the battery.
Residual current management
The residual current management reduces
power consumption while the vehicle is
parked. It controls the supply of power to the
various electrical devices while the ignition is
switched off. The system takes the battery di-
agnosis data into consideration.
Depending on the power level of the battery,
switch off the individual electrical devices
one after the other to prevent the battery
from losing too much charge and to ensure
that the engine can be started reliably.
Dynamic power management
While the vehicle is moving, this function dis-
tributes the available power to the various
electrical devices and systems according to
their requirements. The power management
ensures that on-board systems do not con-
sume more electrical power than the alterna-
tor can supply, and thus maintains the maxi-
mum possible battery power level. Note

Wheels
convenience functions, such as remote vehi-
cl e opening, may not be av
ailable under cer-
tain circumstances. These functions will be
restored when you switch on the ignition and
start the engine.
With the engine switched off
For example, if you listen to the sound system
with the engine switched off the battery will
run down.
If the energy consumption means there is a
risk that the engine will not start, a text will
appear in vehicles with a driver information
system*.
This driver indicator tells you that you must
start the engine so that the battery can re-
charge.
When the engine is running
Although the alternator generates electrical
power, the battery can still become dis-
charged while the vehicle is being driven. This
can occur when a lot of power is being con-
sumed but only a small amount supplied, es-
pecially if the battery is not fully charged ini-
tially.
To restore the necessary energy balance, the
system will then temporarily shut off the elec-
trical devices that are using a lot of power, or
reduce the current they are consuming. Heat-
ing systems in particular use a large amount
of electrical power. If you notice, for instance, that the seat heating* or the rear window
heater is not w
orking, they may have been
temporarily switched off or regulated to a
lower heat output. These systems will be
available again as soon as sufficient electri-
cal power is available.
You may also notice that the engine runs at a
slightly faster idling speed when necessary.
This is quite normal, and no cause for con-
cern. The increased idling speed allows the
alternator to meet the greater power require-
ment and charge the battery at the same
time. Wheels
Wheel s and t
yres
General notes

Practical tips
Low profile tyres
L o
w profile tyres have a wider tread, a larger
wheel diameter and a lower sidewall height.
Therefore, its driving behaviour is more agile.
Low profile tyres may deteriorate more quick-
ly than standard tyres, for instance due to
strong knocks, potholes, manhole covers and
kerbs. Correct tyre pressure is very important
››› page 348.
To avoid damage to tyres and wheels, drive
with special care when driving on roads in
poor condition.
Visually check your wheels every 3000 km.
If the tyres or rims have received a heavy im-
pact or have been damaged, have a special-
ised workshop check whether or not it is nec-
essary to change the tyre.
Low profile tyres may deteriorate more quick-
ly than standard tyres.
Concealed damage
Damage to tyres and rims is often not readily
visible. If you notice unusual vibration or the
car pulling to one side, this may indicate
that one of the tyres is damaged. Reduce
speed immediately if there is any reason to
suspect that damage may have occurred. In-
spect the tyres for damage. If no external
damage is visible, drive slowly and carefully
to the nearest specialised workshop and
have the car inspected. Foreign objects inserted in the tyre

Wheels
New wheels and tyres It is best to have all wheels and tyres serviced
by a specialised w
orkshop
. There they have
the required knowledge, the special tools and
the corresponding spare parts.

Practical tips

Wheels
Driving style
F ast cornering, heavy accel
eration and hard
braking (squealing tyres) all increase tyre
wear.
Wheel balance
The wheels on new vehicles are balanced.
However, certain circumstances may lead to
imbalance (run-out), which is detected as vi-
brations in the steering wheel.
Unbalanced wheels should be rebalanced,
as they otherwise cause excessive wear on
steering, suspension and tyres. A wheel must
also be rebalanced when a new tyre is fitted
or if a tyre is repaired.
Incorrect wheel alignment
Incorrect running gear alignment causes ex-
cessive tyre wear, impairing the safety of the
vehicle. If you notice excessive tyre wear, you
should check wheel alignment at a SEAT Of-
ficial Service. WARNING
Unsuitable handling of the wheels and
t yr

es may lead to sudden tyre pressure los-
ses, to tread separation or even to a blow-
out.

Practical tips
The minimum permitted profile depth 1)
hav e
been r eached when the tyres have worn
down to the wear indicators. Replace the
tyres with new ones ››› .
Changing wheel s ar

ound
To ensure that the wear is equal on all tyres
the wheels should be changed round from
time to time according to the system
››› Fig. 236. The useful life of all the tyres will
then be about the same time. WARNING
The tyres must be replaced at the latest
when the tr ead is w

orn down to the tread
wear indicators. Failure to follow this in-
struction could result in an accident.