traction control Hyundai Ioniq Hybrid 2020 - RHD (UK, Australia) User Guide

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Maintenance
4. Tyre ply composition and
material
The number of layers or plies of rub-
ber-coated fabric in the tyre. Tyre
manufacturers also must indicate the
materials in the tyre, which include
steel, nylon, polyester, and others.
The letter "R" means radial ply con-
struction; the letter "D“ means diago-
nal or bias ply construction; and the
letter "B" means belted-bias ply con-
struction.
5. Maximum permissible infla-
tion pressure
This number is the greatest amount
of air pressure that should be put in
the tyre. Do not exceed the maximum
permissible inflation pressure. Refer
to the Tyre and Loading Information
label for recommended inflation
pressure.
6. Maximum load rating
This number indicates the maximum
load in kilograms and pounds that
can be carried by the tyre. When
replacing the tyres on the vehicle,
always use a tyre that has the same
load rating as the factory installed
tyre.
7. Uniform tyre quality grading
Quality grades can be found where
applicable on the tyre sidewall
between tread shoulder and maxi-
mum section width.
For example:
TREADWEAR 200
TRACTION AA
TEMPERATURE A
Tread wear
The tread wear grade is a compara-
tive rating based on the wear rate of
the tyre when tested under controlled
conditions on a specified govern-
ment test course. For example, a tyre
graded 150 would wear one-and-a-
half times (1½) as well on the gov-
ernment course as a tyre graded
100.
The relative performance of tyres
depends upon the actual conditions
of their use, however, and may
depart significantly from the norm
due to variations in driving habits,
service practices and differences in
road characteristics and climate.
These grades are molded on the
sidewalls of passenger vehicle tyres.
The tyres available as standard or
optional equipment on your vehicle
may vary with respect to grade.

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Maintenance
Traction - AA, A, B & C
The traction grades, from highest to
lowest, are AA, A, B and C. Those
grades represent the tyre’s ability to
stop on wet pavement as measured
under controlled conditions on spec-
ified government test surfaces of
asphalt and concrete. A tyre marked
C may have poor traction perform-
ance.
Temperature - A, B & C
The temperature grades are A (the
highest), B and C representing the
tyre’s resistance to the generation of
heat and its ability to dissipate heat
when tested under controlled condi-
tions on a specified indoor laboratory
test wheel.
Sustained high temperature can
cause the material of the tyre to
degenerate and reduce tyre life, and
excessive temperature can lead to
sudden tyre failure. Grades B and A
represent higher levels of perform-
ance on the laboratory test wheel
than the minimum required by law. The traction grade assigned to
this tyre is based on straight-
ahead braking traction tests,
and does not include accelera-
tion, cornering, hydroplaning,
or peak traction characteristics.
WARNING
The temperature grade for this
tyre is established for a tyre that
is properly inflated and not
overloaded. Excessive speed,
under-inflation, over-inflation,
or excessive loading, either
separately or in combination,
can cause heat build-up and
possible sudden tyre failure.
This may cause loss of vehicle
control resulting in an accident.
WARNING