Mercedes-Benz A-Class Series Owner's Manual page 247

Tyre pressure
244
If a tyre size precedes a tyre pressure, the tyre
pressure information following is only valid
for that tyre size.
Instead of the complete tyre size, the rim
diameter alone, for example R16, may be lis-
ted.
Rim diameter : is part of the tyre size and
can be found on the tyre sidewall.
G
Risk of accident
Tyre pressure that is either too high or too low
has a negative effect on the vehicle's driving
safety, which could lead you to cause an acci-
dent. Therefore, you should regularly check
the pressure of all the tyres, particularly prior
to long trips, and correct the pressure as nec-
essary.
To test tyre pressure, use a suitable pressure
gauge. The outer appearance of a tyre does
not permit any reliable conclusion about the
tyre pressure.
G
Risk of accident
Do not fit anything else to the tyre valve other
than the standard valve cap. In particular, ret-
rofitted tyre pressure monitors which are
screwed on to the valve may overload it and
cause it to fail. Due to their design, the valve
is kept open continuously, which may lead to
air loss.
G
Risk of accident
Should the tyre pressure drop repeatedly:
check the tyre for foreign bodies.
R
check whether the wheel is losing air or the
R
valve is leaking.
make sure that only a valve cap approved
R
by Mercedes-Benz is fitted on the tyre
valve.
Tyre pressures that are too low have a nega-
tive effect on vehicle safety, which could lead
you to cause an accident.
If possible, only correct tyre pressures when
the tyres are cold. Depending on the ambient
temperature, the speed you are driving at and
the load on the tyres, the tyre temperature
and thus the tyre pressure may change by
approximately 10 kPa (0.1 bar, 1.5 psi) per
10 †. Take this into account when checking
the pressure of warm tyres and only correct
it if it is too low for the current operating con-
ditions.