2005 MERCEDES-BENZ CLK500 CABRIOLET check engine

309 Operation
Engine compartment
Adding engine oil
1Filler cap

Unscrew filler cap1 from filler neck.

Add engine oil as required. Be careful
not to overfill with oil.
Be careful not to spill any oil when adding.
Avoid environmental damage caused by oil
entering the ground or water.

Screw filler cap1 back on filler neck.
More information on engine oil can be
found in the “Technical data” section
(
page 453) and (
page 455).
Transmission fluid level
The transmission fluid level does not need
to be checked. If you notice transmission
fluid loss or gear shifting malfunctions,
have an authorized Mercedes-Benz Center
check the automatic transmission.
!Only use approved engine oils and oil
filters required for vehicles with
Maintenance System (U.S. vehicles) or
FSS (Canada vehicles). For a listing of
approved engine oils and oil filters,
refer to the Factory Approved Service
Products pamphlet in your vehicle
literature portfolio, or contact an
authorized Mercedes-Benz Center.
Using engine oils and oil filters of
specification other than those
expressly required for the Maintenance
System (U.S. vehicles) or FSS (Canada
vehicles), or changing of oil and oil filter
at change intervals longer than those
called for by the Maintenance System
(U.S. vehicles) or FSS (Canada vehi-
cles) will result in engine damage not
covered by the Mercedes-Benz Limited
Warranty.
!Excess oil must be siphoned or drained
off. It could cause damage to the
engine and catalytic converter not
covered by the Mercedes-Benz Limited
Warranty.

310 OperationEngine compartmentCoolant
The engine coolant is a mixture of water
and anticorrosion/antifreeze. To check
the coolant level, the vehicle must be
parked on level ground and the engine
must be cool.
The coolant expansion tank is located on
the passenger side of the engine
compartment.
1Coolant expansion tank
2Cap

Using a rag, turn cap2 slowly approx-
imately one half turn to the left to re-
lease any excess pressure.

Continue turning the cap2 to the left
and remove it.
The coolant level is correct if the level


for cold coolant: reaches the black top
part of the reservoir


for warm coolant: is approx. 0.6 in
(1.5 cm) higher

Add coolant as required.

Replace and tighten cap2.
More information on coolant can be found
in the “Technical data” section
(
page 458).
Warning!
G
In order to avoid any possibly serious burns:

Use extreme caution when opening the
hood if there are any signs of steam or
coolant leaking from the cooling system,
or if the coolant temperature gauge indi-
cates that the coolant is overheated.


Do not remove pressure cap on coolant
reservoir if the coolant temperature is
above 158°F (70°C). Allow the coolant
to cool down before removing cap. The
coolant reservoir contains hot fluid and
is under pressure.


Using a rag, slowly open the cap approx-
imately
1/2 turn to relieve excess pres-
sure. If opened immediately, scalding
hot fluid and steam will be blown out un-
der pressure.


Do not spill antifreeze on hot engine
parts. Antifreeze contains ethylene gly-
col which may burn if it comes into con-
tact with hot engine parts.

311 Operation
Engine compartment
Battery
Your vehicle’s battery is located in the
engine compartment on the right-hand
side (
page 427).
The battery should always be sufficiently
charged in order to achieve its rated
service life. Refer to Maintenance Booklet
for battery maintenance intervals.
If you use your vehicle mostly for
short-distance trips, you will need to have
the battery charge checked more
frequently.
When replacing the battery, always use
batteries approved by Mercedes-Benz.
If you do not intend to operate your vehicle
for an extended period of time, consult an
authorized Mercedes-Benz Center about
steps you need to observe.Batteries contain materials that can harm
the environment if disposed of improperly.
Recycling of batteries is the preferred
method of disposal. Many states require
sellers of batteries to accept old batteries
for recycling.
G
Observe all safety instructions
and precautions when handling
automotive batteries.
A
Risk of explosion.
D
Keep flames or sparks away
from battery. Do not smoke.
B
Battery acid is caustic. Do not
allow it to come into contact
with skin, eyes or clothing.
In case it does, immediately
flush affected area with clean
water and seek medical help if
necessary.
E
Wear eye protection.
C
Keep children away.
F
Follow the instructions in this
Operator's Manual.

340 OperationWinter drivingBefore the onset of winter, have your
vehicle winterized at an authorized
Mercedes-Benz Center. This service
includes:

Check of anticorrosion and antifreeze
concentration.


Addition of cleaning concentrate to the
water of the windshield and headlamp
cleaning system. Add MB Concentrate
“S” to a premixed windshield washer
solvent / antifreeze which is formulated
for temperatures below freezing point
(page 460).


Battery test. Battery capacity drops
with decreasing ambient temperature.
A well charged battery helps to make
sure that the engine can be started
even at low ambient temperatures.


Tire change. Mercedes-Benz recom-
mends M+S rated radial-ply tires with a
minimum tread depth of approximately 1/6 in (4 mm) on all four wheels for the
winter season.
Winter tires
Always use winter tires at temperatures
below 45°F (7°C) and whenever wintry
road conditions prevail. Use of winter tires
is the only way to achieve the maximum
effectiveness of the ABS and the ESP in
winter operation.
For safe handling, make sure that all
mounted winter tires are of the same make
and have the same tread design.Always observe the speed rating of the
winter tires installed on your vehicle. If the
maximum speed for which your tires are
rated is below the speed rating of your ve-
hicle, you must place a notice to this effect
where it will be seen by the driver. Such no-
tices are available at your tire dealer or any
authorized Mercedes-Benz Center.Warning!
G
Winter tires with a tread depth under
1/6in
(4 mm) must be replaced. They are no
longer suitable for winter operation.
Warning!
G
If you use your spare tire when winter tires
are fitted on the other wheels, be aware that
the difference in tire characteristics may
very well impair turning stability and that
overall driving stability may be reduced.
Adapt your driving style accordingly.
Have the spare tire replaced with a winter
tire at the nearest authorized
Mercedes-Benz Center.

341 Operation
Winter driving
Block heater* (Canada only)
The engine is equipped with a block
heater.
The electrical cable may be installed at an
authorized Mercedes-Benz Center.
Snow chains
Snow chains should only be driven on
snow-covered roads at speeds not to
exceed 30 mph (50 km/h). Remove chains
as soon as possible when driving on roads
without snow.
Please observe the following guidelines
when using snow chains:

Using snow chains is not permissible
with all wheel/tire combinations.


Snow chains should only be used on
the rear wheels. Follow the manufac-
turer's mounting instructions.


Only use snow chains that are
approved by Mercedes-Benz. Your
authorized Mercedes-Benz Center will
be glad to advise you on this subject.


Use of snow chains may be prohibited
depending on location. Always check
local and state laws before installing
snow chains.
iWhen driving with snow chains, you
may wish to deactivate the ESP
(page 87) before setting the vehicle
in motion. This will improve the
vehicle‘s traction.
!Use of snow chains is not permissible
with tire sizes:

225/50 R16 92H


245/40 R17 91W


245/40 R17 91Y


255/35 R18 94Y


T 125/90 R 16 98M


T 125/80 R17 99M

355 Practical hints
What to do if …?
Problem
Possible cause
Suggested solution
;
3
(USA only)
(Canada only)
The red brake warning lamp
comes on while driving and you
hear a warning sound.
You are driving with the
parking brake set.

Release the parking brake
(page 49).
;
3
(USA only)
(Canada only)
The red brake warning lamp
comes on while driving.
There is insufficient brake
fluid in the reservoir.

Risk of accident! Carefully stop the
vehicle and notify an authorized
Mercedes-Benz Center. Do not add
brake fluid! This will not solve the
problem.
Warning!
G
Driving with the brake warning lamp illumi-
nated can result in an accident. Have your
brake system checked immediately if the
brake warning lamp stays on. Do not add
brake fluid before checking the brake
system.
Overfilling the brake fluid reservoir can re-
sult in spilling brake fluid on hot engine
parts and the brake fluid catching fire. You
can be seriously burned.
!If you find that the brake fluid in the
brake fluid reservoir has fallen to the
minimum mark or below, have the
brake system checked for brake pad
thickness and leaks.

356 Practical hintsWhat to do if …?Problem
Possible cause
Suggested solution
ú
±
(USA only)
(Canada only)
The yellow engine
malfunction indi-
cator lamp comes
on while driving.
There is a malfunction in:

The fuel management system


The ignition system


The emission control system


Systems which affect emissions
Such malfunctions may result in ex-
cessive emissions values and may
switch the engine to its Limp-Home
Mode (emergency operation).

Have the vehicle checked as soon as possi-
ble by an authorized Mercedes-Benz Center.
An on-board diagnostic connector is used by
the service station to link the vehicle to the
shop diagnostics system. It allows the accu-
rate identification of system malfunctions
through the readout of diagnostic trouble
codes. It is located in the front left area of the
footwell next to the parking brake pedal.
A loss of pressure has been
detected in the fuel system. The fuel
cap may not be closed properly or
the fuel system may be leaky.

Check the fuel cap (
page 302).
If it is not closed properly:

Close the fuel cap.
If it is closed properly:

Have the fuel system checked by an autho-
rized Mercedes-Benz Center.
Your fuel tank is empty.

After refuelling, start turn off and restart the
engine three or four times in succession.
The Limp-Home mode is canceled. You do not
need to have your vehicle checked.

357 Practical hints
What to do if …?
Problem
Possible cause
Suggested solution
•
The red coolant warning lamp
comes on when the engine is
running.
There is insufficient coolant in the reservoir.

Add coolant to prevent engine from
overheating (
page 310).
If this warning lamp comes on frequently,
there is a leak in the cooling system.

Have the cooling system checked.
If the coolant level is correct, the electric ra-
diator fan may be broken.

If the coolant temperature is below
257 °F (125 °C), you can continue
driving to the nearest authorized
Mercedes-Benz Center.

Avoid high engine loads (e.g. driving
uphill) and stop-and-go driving.
•
The red coolant warning lamp
comes on while driving and you
hear a warning sound.
The coolant temperature has exceeded
257 °F (125 °C).

Stop as soon as possible and allow
the engine and coolant to cool down.
Warning!
G
Driving when your engine is badly overheat-
ed can cause some fluids which may have
leaked into the engine compartment to
catch fire. You could be seriously burned.
Steam from an overheated engine can cause
serious burns and can occur just by opening
the hood. Stay away from the engine if you
see or hear steam coming from it.
Turn off the engine, get out of the vehicle
and do not stand near the vehicle until the
engine has cooled down.