2008 MERCEDES-BENZ GLK SUV coolant temperature

Problem
Possible causes/consequences and
X
X Solutions ?
The red coolant
warning lamp
comes on while
the engine is
running. A warn-
ing tone also
sounds. The coolant temperature has exceeded 130 †. The airflow to the
radiator may be blocked or the coolant level may be too low.
The engine is not being cooled sufficiently and may be damaged.
X
Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Allow the engine and coolant to cool.
X Make sure that the air supply to the radiator is not blocked, e.g.
by slush.
X Check the coolant level (Y page 149). Observe the warning
notes.
X If necessary, top up the coolant.
X Have the engine cooling system checked at a qualified specialist
workshop if the coolant needs topping up more often than usual.
If the coolant level is correct, the electric radiator fan may be
faulty.
X Do not continue driving under any circumstances.
X Consult a qualified specialist workshop. ;
The yellow
engine diagnos-
tics warning
lamp lights up
while the engine
is running. Vehicles with a diesel engine: the fuel tank has been run dry.
X
Start the engine three to four times after refuelling.
Emergency running mode is cancelled. The vehicle need not be
checked. ;
The yellow
engine diagnos-
tics warning
lamp lights up
while the engine
is running. There may be a fault, for example
R
in the engine management
R in the ignition system
R in the exhaust system
R in the ignition system (for vehicles with petrol engines)
The emission limit values may be exceeded and the engine can
run in emergency mode.
X Have the vehicle checked as soon as possible at a qualified
specialist workshop. 7
The red seat belt
warning lamp
lights up for 6
seconds after
the engine starts
up31
. The seat belt warning lamp reminds the driver and front passenger
to fasten their seat belts.
X Fasten your seat belt (Y page 70). Troubleshooting
203Practical advice
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Problem
Possible causes/consequences and
X XSolutions The engine will not
start. You cannot hear
the starter motor oper-
ating. The on-board voltage is too low because the starter battery is too
weak or discharged.
X
Jump-start the vehicle (Y page 234).
If the engine does not start despite attempting to jump-start it:
X Consult a qualified specialist workshop. The starter motor was exposed to a thermal load that was too high.
X
Allow the starter motor to cool down for approximately two
minutes.
X Try to start the engine again.
If the engine still does not start:
X Consult a qualified specialist workshop. Vehicles with a petrol
engine:
The engine is not run-
ning smoothly and is
misfiring. There is a malfunction in the engine electronics or a mechanical
component of the engine control unit.
X
Only depress the accelerator pedal slightly.
X Have the cause rectified immediately at a qualified specialist
workshop.
Otherwise, non-combusted fuel may get into the catalytic con-
verter and damage it. The coolant tempera-
ture gauge shows a
value above 120 †.
The coolant warning
lamp may also light up
and a warning tone may
sound (Y
page 90). The coolant level is too low. The coolant is too hot and the engine
is no longer being cooled sufficiently.
X
Stop as soon as possible and allow the engine and the coolant
to cool down.
X Check the coolant level (Y page 149). Observe the warning
notes as you do so and top up the coolant if necessary. If the coolant level is correct, the radiator fan may be faulty. The
coolant is too hot and the engine is no longer being cooled suffi-
ciently.
X
If the coolant temperature is less than 120 †, you can continue
driving to the nearest qualified specialist workshop.
X Avoid heavy loads on the engine as you do so, e.g. driving on
mountain roads and stop/start driving. 208 TroubleshootingPractical advice
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R
engine oil brand
R grade (MB Sheet number)
R SAE classification (viscosity)
is not available, you can use another min-
eral or synthetic engine oil which has been
approved by Mercedes-Benz. You must
then have an oil change carried out at the
earliest possible opportunity.
Mixing oils reduces the benefits of high-
grade engine oil.
! Do not use lubricant additives as they can
lead to increased wear and damage to
mechanical assemblies. The use of lubri-
cant additives will result in a restriction of
your warranty.
! Engine oils for vehicles without a diesel
particle filter may also be used temporarily
in vehicles with a diesel particle filter if the
engine oil listed is not available. You must
then have an oil change carried out as soon
as possible.
Engine oil viscosity Viscosity describes the flow characteristics
of a fluid. If an engine oil has a high viscosity, this means it is thick; a low viscosity means
that it is thin.
Select the SAE classification (viscosity) of the
engine oil according to the outside tempera-
ture. The following table shows you the vis-
cosity classes to be used depending on the
average air temperature. Capacities
The following values refer to an oil change
including the oil filter.
Engine with oil fil-
ter GLK 280 GLK 350 GLK 320 CDI
Replacement
amount
7.0 l 7.0 l 8.0 l
Coolant
The coolant is a mixture of water and anti-
freeze/corrosion inhibitor. It performs the
following tasks:
R anti-corrosion protection
R antifreeze protection
R raising the boiling point
i When the vehicle is first delivered, it is
topped up with a coolant that will ensure adequate antifreeze and corrosion protec-
tion.
! Only top up with coolant that has been
premixed with the desired antifreeze pro-
tection. Otherwise, you could damage the
engine.
Further information on coolants and on fill-
ing can be found in the Mercedes-Benz
Specifications for Service Products, sheet Service products and capacities
247Technical data
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310.1, or at any Mercedes-Benz Service
Centre.
! Always use a suitable coolant mixture,
even in countries where high temperatures
prevail.
Otherwise, the cooling system will not be
sufficiently protected from corrosion, and
the boiling point will be too low.
If antifreeze/corrosion inhibitor is present in
the correct concentration, the boiling point of
the coolant will be around 130 °C.
The antifreeze/corrosion inhibitor concentra-
tion in the cooling system should:
R be at least 50%. This will protect the cooling
system against freezing down to around
–37 °C.
R not exceed 55% concentration (antifreeze
protection down to –45 °C); otherwise,
heat will not be effectively dissipated. If the vehicle has lost coolant, top it up with
equal amounts of water and antifreeze/cor-
rosion inhibitor. Mercedes-Benz recom-
mends an antifreeze/corrosion inhibitor
which has been approved for Mercedes-Benz.
!
The cooling system contains a supply
which must be renewed after 15 years, or
after 250, 000 km at the latest.
The warranty is only valid if you top up with
an antifreeze/corrosion inhibitor which
has been approved by Mercedes-Benz and
the recommended mixture ratio is
observed.
Capacities The following values indicate the total cooling
system capacities.
GLK 280 GLK 350 GLK 320 CDI
Coolant
8.4 l 8.4 l 11.5 l
Amount of antifreeze/corrosion inhibitor required for antifreeze protection
Down to –37 °C
(approx. 50%)
4.2 l 4.2 l 5.75 l
Down to –45 °C
(approx. 55%)
4.6 l 4.6 l 6.3 l
Brake fluid
Over a period of time, the brake fluid absorbs
moisture from the air; this lowers its boiling
point. G
Risk of accident
If the boiling point of the brake fluid is too low,
vapour pockets may form in the brake system
when the brakes are applied hard (e.g. when
driving downhill). This would impair braking
efficiency.
Have the brake fluid renewed every two years
with a brake fluid that has been approved by Mercedes-Benz and have this confirmed in
the Service Booklet.
i There is usually a notice in the Engine,
Compartment to remind you when the next
brake fluid change is due. 248 Service products and capacitiesTechnical data
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