Page 191 of 259

Inspecting and replenishing 190If the coolant level in the reservoir is too low, this is indicated by the warning light
in the instrument cluster
⇒page 29. We nevertheless recommend inspecting
the coolant level directly at the reservoir from time to time.
Loss of coolant
A loss of coolant is first and foremost an indication of a leak in the system. You
should not merely top up the coolant in the reservoir. It is also important to have
the cooling system inspected without delay by a specialist garage.
Losses can only occur through the pressure relief in the cap of the coolant expan-
sion bottle which is completely free of leaks if the coolant boils as a result of over-
heating and is forced out of the cooling system.
WARNING
Read and observe the warning notes ⇒page 185, “Working in the engine
compartment” before working in the engine compartment.
Caution
One should contact a specialist garage as soon as possible if the source of over-
heating itself cannot be determined and removed, since there may be grave
damage to the engine.Replenishing the coolant– Switch the engine off.
– Allow the engine to cool down.
– Place a cloth over the cap of the coolant expansion reservoir
⇒page 189, fig. 184 and unscrew the cap carefully by turning it to the
left ⇒.
– Top up the coolant.
– Screw the cap tight until it is heard to lock.
The coolant which you use for replenishing the system, must comply with one
specific specification ⇒page 189, “Coolant”. Do not use an alternative additive if
the coolant additive G12 PLUS - PLUS is not available in exceptional cases. Just top
up the system with water and as soon as possible arrange adjustment to correct the
mixing ratio of water and coolant additive again by a specialist garage.
Only use fresh coolant for topping up the system.
Do not fill up over the “MAX” marking! Excess coolant which is heated up is forced
out of the cooling system through the pressure relief valve in the cap of the coolant
compensation bottle.
Wait until the engine has cooled down for a system which has suffered a major loss
of coolant before pouring in coolant. This is necessary to avoid engine damage.
WARNING
•
The cooling system is pressurized! Do not open the cap of the coolant
expansion bottle if the engine is still hot - risk of scalding!
•
The coolant additive and thus all of the coolant is harmful to your health.
Avoid contact with the coolant. Coolant vapours are also harmful to the
health. It is important, therefore, to always safely store any coolant additive
in its original container out of the reach of children - risk of poisoning!
•
If any splashes of coolant get into your eyes, rinse out your eyes immedi-
ately with clear water and contact a doctor as soon as possible.
•
You should also consult a doctor without delay if you have inadvertently
swallowed coolant.Caution
Do not continue your journey if for some reason it is not possible under the
conditions prevailing to top up with coolant. witch the engine off and obtain
professional assistance from a specialist garage.
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Page 199 of 259

Wheels and Tyres 198Wheels and TyresWheelsGeneral information•
New tyres do not offer optimal grip at first and should therefore be run in for
about 500 km at a moderate speed and an appropriately cautious style of driving.
You will also profit from longer tyre life.
•
The tread depth of new tyres may differ because of design features and the
configuration of the tread (depending on the type of tyre and the manufacturer).
•
Drive over curbs on the side of the road and other such obstacles slowly and,
where possible, at a right angle in order to avoid damage to tyres and wheel trims.
•
Inspect your tyres from time to time for damage (punctures, cuts, splits and
bulges). Remove foreign bodies from the tyre profile.
•
Damage to tyres and wheels is frequently not visible. Unusual vibrations or
pulling of the vehicle to one side could be a sign of tyre damage. Please reduce
your speed immediately and stop if you suspect that a wheel is damaged.
Inspect the tyres for signs of damage (bulges, splits, etc.). If no visible damage is
present, please drive at an appropriately slow speed and carefully to the nearest
specialist garage in order to have your vehicle inspected.
•
Also protect your tyres from contact with oil, grease and fuel.
•
Immediately replace any dust caps of the valves which have got lost.
•
Mark wheels before removing them so that their previous direction of running
can be maintained when mounted them again.
•
Always store wheels or tyres which been removed in a cool, dry and, where
possible, dark place. Tyres which are not fixed to a wheel trim should be stored
upright.
Unidirectional tyres*
The direction of rotation of the tyres is marked by arrows on the wall of the tyre. This
indicates the direction of rotation of the tyre, and it is essential that the tyres are
fitted on to run in this direction. Only then are the tyres able to provide the optimal
properties in terms of grip, low noise, wear-and-tear and aquaplaning.Further information concerning the use of unidirectional tyres ⇒page 202.
WARNING
•
New tyres during the first 500 km do not offer optimal grip and should
therefore be run appropriately - risk of accident!
•
Never drive with damaged tyres - risk of accident!Note
Please observe the various differing legal requirements regarding tyres.Tyre lifeThe life of your tyres very much depends on the following points:
Tyre pressure
The working life of tyres will be shortened considerably if the tyres are insufficiently
or over-inflated and this will have an adverse effect on the handling of your vehicle.
Correctly inflated tyres are of particular importance when travelling at high speeds.
It is therefore good to check the pressure at least once a month and also before
Fig. 190 An opened fuel filler
flap with a tyre size and tyre
inflation pressure table
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Page 209 of 259

Breakdown assistance 208
– Tighten the wheel bolts firmly, alternately and diagonally using the
wheel wrench ⇒page 209.
– Mount the full wheel trim/wheel trim cap or the caps.
Note•
All bolts must be clean and must turn easily.
•
You must never grease or oil the wheel bolts!
•
When fitting on unidirectional tyres, ensure that the tyres rotate in the correct
direction ⇒page 198.
Subsequent stepsAfter changing the wheel, you must perform the following steps.
– Stow and attach the replaced wheel in the spare wheel well.
– Stow the vehicle tool kit in the space provided.
–Check the tyre pressure on the spare wheel just mounted as soon as
possible.
– Have the tightening torque of the wheel bolts checked with a torque
wrench as soon as possible. The tightening torque for steel and light
alloy wheels must be 120 Nm.
– Have the defective tyre repaired as soon as possible.
WARNING
It is necessary to observe the guidelines given on ⇒page 200, “New tyres
and wheels” if the vehicle is subsequently fitted with tyres which are
different to those it was fitted with at the works.
Note
•
If you find, when changing the wheel, that the wheel bolts are corroded and
difficult to turn, the bolts must be replaced before checking the tightening torque.
•
Drive cautiously and only at a moderate speed to a workshop where the tight-
ening torque can be checked.
Full wheel trim*Pulling off
– Hook the clamp found in the vehicle tool kit into the reinforced edge
of the full wheel trim.
– Push the wheel key through the clamp, support the wheel key on the
tyre and pull off the wheel trim ⇒fig. 195.
Installing
– First press the full wheel trim onto the wheel at the valve opening
provided. Then press the full wheel trim into the wheel in such a way
that its entire circumference locks correctly in place.
Fig. 195 Removing the full
wheel trim
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