2008 MERCEDES-BENZ CLS500 Owner's Manual

376 Practical hints
What to do if …
During severe operation conditions and
stop-and-go city traffic, the coolant tem-
perature may rise close to 248°F (120°C).
Display symbolDisplay messagePossible cause/consequencePossible solution
DCoolant
Stop Vehicle,
turn engine off.The coolant is too hot.Stop the vehicle in a safe location or as soon
as it is safe to do so and immediately turn
off the engine.
Only start the engine again after the mes-
sage disappears. You could otherwise dam-
age the engine.
Apply the parking brake (page 53).
Observe the coolant temperature indicator
in the instrument cluster (
page 26).
If the temperature rises again:
Contact an authorized Mercedes-Benz
Center immediately.
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 engine hood. Stay away from the engine
if you see or hear steam coming from it.
Stop the vehicle in a safe location away from
other traffic. Turn off the engine, get out of
the vehicle and do not stand near the vehicle
until the engine has cooled down.
!The engine should not be operated with the
coolant temperature above 248°F (120°C).
Doing so may cause serious damage which is not
covered by the Mercedes-Benz Limited
Warranty.

377 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
DCoolant
Stop Vehicle,
turn engine off.The poly-V-belt could be broken.Stop the vehicle in a safe location and immediately
turn off the engine.
Check the poly-V-belt.
If it is broken:
Do not continue to drive. Otherwise the engine will
overheat due to an inoperative water pump which
may result in damage to the engine. Notify an au-
thorized Mercedes-Benz Center.
If it is intact:
Do not continue to drive the vehicle with this mes-
sage displayed. Doing so could result in serious en-
gine damage that is not covered by the
Mercedes-Benz Limited Warranty.
Observe the coolant temperature indicator in the
instrument cluster (
page 26).
Drive immediately to the nearest authorized
Mercedes-Benz Center.

378 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
DThe cooling fan for the coolant is
malfunctioning.Observe the coolant temperature indicator in the
instrument cluster (
page 26).
If the coolant temperature is under 248°F (120°C),
you may continue driving to an authorized
Mercedes-Benz Center.
Avoid placing heavy loads on the engine (e.g. by
driving uphill) as well as stop-and-go traffic.
Have the fan replaced as soon as possible.
± Display Malfunction
Service RequiredCertain electronic systems are
unable to relay information to
the control system. The follow-
ing systems may have failed:

Coolant temperature display

Tachometer

Cruise control display
Have the electronic systems checked by an autho-
rized Mercedes-Benz Center.
Engine
ServiceThere may be a malfunction in:

the fuel injection system

the ignition system

the exhaust system
Have the engine checked as soon as possible by an
authorized Mercedes-Benz Center.

379 Practical hints
What to do if …
When the Check oil level at next re-
fueling.
message appears while the en-
gine is running and at operating
temperature, the engine oil level has
dropped to approximately the minimum
level.
When this occurs, the warning will first
come on intermittently and then stay on if
the oil level drops further.If no oil leaks are noted, continue to drive
to the nearest service station where the
engine oil should be topped to the required
level with an approved engine oil.
For information on approved engine oils,
refer to the Factory Approved Service
Products pamphlet (USA only) or contact
an authorized Mercedes-Benz Center.
Display symbolDisplay messagePossible cause/consequencePossible solution
: Check oil level
at next refueling
.
There is no oil in the engine. There is
a danger of engine damage.Check the engine oil level (page 288) and
add engine oil as required (
page 289).
If you must add engine oil frequently, have
the engine checked for possible leaks.
!The engine oil level warnings should not be
ignored. Extended driving with the symbol dis-
played could result in serious engine damage
that is not covered by the Mercedes-Benz Limit-
ed Warranty.

380 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
A Reserve FuelThe fuel level has dropped below the re-
serve mark.Refuel at the next gas station
(
page 283).
Gas Cap
Is OpenA 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 283).
If it is not closed properly:
Close the fuel cap.
If it is closed properly:
Have the fuel system checked by an au-
thorized Mercedes-Benz Center.
»Replace
Air FilterThe air cleaner is clogged.Have the air cleaner checked by an au-
thorized Mercedes-Benz Center.
FRemove KeyYou have forgotten to remove the
SmartKey.Remove the SmartKey from the starter
switch.
Please
get a new key.The SmartKey is malfunctioning.Contact an authorized Mercedes-Benz
Center.
Key Detected
In VehicleA SmartKey with KEYLESS-GO* left in the
vehicle was recognized while locking the
vehicle from the outside.Take the SmartKey with KEYLESS-GO*
out of the vehicle.

381 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
FPlease don’t
forget your key.This display appears (for a maximum of
60 seconds) if the driver’s door is opened
with the engine turned off and no
SmartKey in the starter switch.
This message is only a reminder.Take the SmartKey or SmartKey with
KEYLESS-GO* with you when leaving
the vehicle.
Change
Key BatteriesThe SmartKey with KEYLESS-GO* batter-
ies are discharged.Replace the batteries (page 402).
Key
Not DetectedThe SmartKey with KEYLESS-GO* is not
recognized while the engine is running
because

the SmartKey with KEYLESS-GO* is
not in the vehicle

there is strong radio-frequency inter-
ference
Stop the vehicle as soon as it is safe to
do so.
Search for the SmartKey.
Otherwise the vehicle cannot be cen-
trally locked nor can the engine be
started again after the engine is
stopped.
Key
Not DetectedThe SmartKey with KEYLESS-GO* is mo-
mentarily not recognized.Change the position of the SmartKey in
the vehicle.
Operate the vehicle with the SmartKey
in the starter switch if necessary.

382 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
. Active Headlamps
InoperativeThe active Bi-Xenon* headlamp system is
malfunctioning.Contact an authorized Mercedes-Benz
Center as soon as possible.
Active HeadlampsThe active Bi-Xenon* headlamps are mal-
functioning.Contact an authorized Mercedes-Benz
Center as soon as possible.
Low Beam
LeftThe left low beam lamp is malfunctioning.Halogen headlamp:
Replace the bulb as soon as possible
(
page 404).
Bi-Xenon* headlamp:
Contact an authorized Mercedes-Benz
Center as soon as possible.
Low Beam
RightThe right low beam lamp is malfunction-
ing.Halogen headlamp:
Replace the bulb as soon as possible.
Bi-Xenon* headlamp:
Contact an authorized Mercedes-Benz
Center as soon as possible.

383 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
.Reverse Lamp
LeftThe left reverse lamp is malfunctioning.Contact an authorized Mercedes-Benz
Center as soon as possible.
Reverse Lamp
RightThe right reverse lamp is malfunctioning.Contact an authorized Mercedes-Benz
Center as soon as possible.
Brake-/Tail Lamp
Left
Auxiliary Bulb OnThe left brake/tail lamp is malfunction-
ing.
This message will only appear if a critical
number of LEDs have stopped working.
An auxiliary bulb is being used.Contact an authorized Mercedes-Benz
Center as soon as possible.
Brake-/Tail Lamp
Right
Auxiliary Bulb OnThe right brake/tail lamp is malfunction-
ing.
This message will only appear if a critical
number of LEDs have stopped working.
An auxiliary bulb is being used.Contact an authorized Mercedes-Benz
Center as soon as possible.
3rd
Brake LampThe high mounted brake lamp is malfunc-
tioning.Contact an authorized Mercedes-Benz
Center as soon as possible.
Front Foglamp
LeftThe left front fog lamp is malfunctioning.Contact an authorized Mercedes-Benz
Center as soon as possible.
Front Foglamp
RightThe right front fog lamp is malfunctioning.Contact an authorized Mercedes-Benz
Center as soon as possible.