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Checking and refilling levels
Opening the bonnet
Fig. 168 Release catch
under the bonnet
Before opening the bonnet make sure that the windscreen wiper
arms are not lifted away from the glass. Otherwise the paint may
be damaged.
– Lift the bonnet slightly ⇒
.
– Press the release catch under the bonnet upwards ⇒ Fig. 168.
This will release the arrester hook under the bonnet.
– Open the bonnet.
The bonnet is held in position by a gas-filled strut.
WARNING
Never open the bonnet if you see steam or drips of coolant being re-
leased from the engine compartment. Failure to comply could result in
burns. Wait until no steam or coolant can be seen before opening the
bonnet.
Work in the engine compartment
Extra caution is necessary when working on components in
the engine compartment.
Always be aware of the danger of injury and scalding as well as the risk of
accident or even fire when working in the engine compartment (e.g. when
checking and refilling fluids). Always observe the warnings listed below
and follow all general safety precautions. The engine compartment of the
vehicle is a potentially hazardous area ⇒
WARNING
● Switch the engine off.
● Remove the ignition key.
● Apply the handbrake firmly.
● If your vehicle is equipped with a manual gearbox, place the gear lev-
er in neutral. If you are driving an automatic vehicle, place the selector
lever in position P.
● Wait for the engine to cool down.
● Children should not be allowed to approach the engine compartment.
● Never spill liquids used for vehicle operation on the engine compart-
ment, as these may catch fire (e.g. coolant).
● Take care not to cause short circuits in the electrical system, especial-
ly when working on the battery.
● Never touch the radiator fan while the engine is hot, as the fan could
start up suddenly.
● Never open the expansion tank when the engine is hot. The cooling
system is under pressure.
● Protect face, hands and arms from any hot steam or hot coolant fluid
released by covering the cap with a large, thick rag when opening the ex-
pansion tank.
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Coolant fluid loss
Any loss of coolant fluid normally indicates a leak in the cooling system. In
this case the cooling system should be inspected by a specialised work-
shop without delay. It is not sufficient merely to top up the coolant fluid.
If there are no leaks in the system, a loss of coolant fluid can only occur if
the coolant boils and is forced out of the system as a result of overheating.
CAUTION
Radiator sealants must not be added to the coolant fluid. Such additives
could seriously impair the function of the cooling system.
Topping up the coolant fluid
Be careful when topping up with coolant fluid. – Switch the engine off.
– Wait for the engine to cool down.
– Cover the cap on the expansion tank ⇒ Fig. 171 with a cloth,
and carefully unscrew the cap anticlockwise ⇒
.
– Add coolant fluid.
– Screw on the cap tightly.
Make sure that the coolant fluid meets the required specifications
⇒ page 231. Do not use a different type of antifreeze if G12++ antifreeze is
not available. In this case, use only water and bring the antifreeze concen-
tration back up to the correct level as soon as possible.
Always top up with new coolant fluid. Do not fill above the “max” mark. Excess coolant fluid is forced out of the
system through the valve in the filler cap when the engine gets hot.
If a lot of coolant fluid has been lost, wait for the engine to
cool down before
putting in cold coolant. Failure to do so could result in serious engine dam-
age.
WARNING
● The cooling system is under pressure. Do not unscrew the cap on the
expansion tank when the engine is hot. Failure to comply could result in
burns.
● The antifreeze and coolant fluid can be a health hazard. Therefore,
the antifreeze should be stored in the original container in a safe place
out of reach of children. Failure to comply could result in poisoning.
For the sake of the environment
Drained off coolant should not be used again. Drain off the used coolant in-
to a suitable container and dispose of it in the proper manner (observe envi-
ronmental regulations).
Radiator fan
The radiator fan can start running spontaneously. The auxiliary fan can continue to run for as long as 10 minutes after stop-
ping the engine, even after the ignition is switched off. It may also start run-
ning suddenly ⇒
after some while if
● Stored heat raises the coolant temperature, or
● The hot engine compartment is additionally heated up by the sun.
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234Checking and refilling levels
WARNING
When working in the engine compartment be aware that the radiator fan
may start running suddenly, leading to the risk of injury.
Washer fluid and windscreen wiper blades Windscreen washer system
Plain water is not sufficient for the windscreen washer sys-
tem.
Fig. 172 In the engine
compartment: Cap of
windscreen washer fluid
reservoir.
The container for the windscreen washer contains the cleaning fluid for the
windscreen and the headlight washer system*. The container is located in
the engine compartment (front left). The filler cap is marked with the symbol
⇒ Fig. 172. The capacity of the container is listed in ⇒ page 296. Plain water on its own is not enough to clean the glass properly. It is there-
fore advisable to add a suitable washer fluid additive (with wax solvent) to
the water. A washer fluid with freeze-resistant additive should be used in
winter.
CAUTION
● Never put radiator antifreeze or other additives into the windscreen
washer fluid.
● Never use washer fluid which contains paint thinners or solvents as it
can damage the paintwork.