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257 Practical hints
What to do if …
Problem
Possible cause
Suggested solution
3
;
(Canada only)
(USA only)The red brake warning lamp
lights up while driving and you
hear a warning sound.
You are driving with the parking brake set.
Release the parking brake (
page 46).
The red brake warning lamp
lights up while driving.
There is insufficient brake fluid in the reser-
voir.
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. Don’t add
brake fluid before checking the brake sys-
tem. Overfilling the brake fluid reservoir can
result 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.
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258 Practical hintsWhat to do if …Problem
Possible cause
Suggested solution
?
The yellow “CHECK ENGINE”
malfunction indicator 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 excessive
emissions values and may switch the engine
to its Limp-home (emergency operation)
mode.
Have the vehicle checked as soon as
possible 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 sys-
tem. It allows the accurate identifica-
tion of system malfunctions through
the readout of diagnostic trouble
codes. It is located in the front left
area of the footwell next to the park-
ing brake pedal.
The fuel cap is not closed tight.
Check the fuel cap.
Your gas tank is empty.
After refuelling start the engine three
or four times in succession.
The limp-home mode is canceled. You do
not need to have your vehicle checked.
<
The red seat belt warning lamp
blinks for a brief period after
starting the engine.
The warning lamp reminds you to fasten seat
belts.
Fasten your seat belt.
The yellow fuel tank reserve warning lamp
lights up while driving.
The fuel level has gone below the reserve
mark.
Refuel at the next gas station
(page 232).
S203 MY03_A.book Page 258 Tuesday, January 28, 2003 2:22 PM
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263 Practical hints
What to do if …
Display
Possible cause
Suggested solution
#
BATTERY/ALTERNATOR
VISIT WORKSHOP!
The battery was charged with a battery
charger or jump started.
Have the battery checked at a service
station.
The battery is no longer charging.
Possible causes:
alternator malfunctioning
broken poly-V-belt
Stop immediately and check the
poly-V-belt.
If it is broken:
Do not continue to drive. Otherwise
the engine will overheat due to an in-
operative water pump which may re-
sult in damage to the engine. Notify an
authorized Mercedes-Benz Center.
If it is intact:
Drive immediately to the nearest au-
thorized Mercedes-Benz Center.
3
(Canada only)
;
(USA only)
BRAKE PAD WEAR
VISIT WORKSHOP!
The brake pads have reached their wear lim-
it.
Have the brake pads replaced as soon
as possible.
!Brake pad thickness must be visually
checked by a qualified technician at the
intervals specified in the Service book-
let.
S203 MY03_A.book Page 263 Tuesday, January 28, 2003 2:22 PM
Page 258 of 370
264 Practical hintsWhat to do if …Display
Possible cause
Suggested solution
3
(Canada only)
;
(USA only)
BRAKE FLUID
VISIT WORKSHOP!
There is insufficient brake fluid in the reser-
voir.
Risk of accident! 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 this message displayed can re-
sult in an accident. Have your brake system
checked immediately. Don’t add brake fluid
before checking the brake system. Overfill-
ing the brake fluid reservoir can result in
spilling brake fluid on hot engine parts and
the brake fluid catching fire. You can be se-
riously 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.
S203 MY03_A.book Page 264 Tuesday, January 28, 2003 2:22 PM
Page 259 of 370
265 Practical hints
What to do if …
Display
Possible cause
Suggested solution
B
COOLANT
CHECK LEVEL!
The coolant level is too low.
Add coolant (
page 238).
If you have to add coolant frequent-
ly, have the cooling system
checked by an authorized
Mercedes-Benz Center.
Warning!
G
Do not spill antifreeze on hot engine parts.
Antifreeze contains ethylene glycol which
may burn if it comes into contact with hot
engine parts. You can be seriously burned.
!Do not ignore the low engine coolant
level warning. Extended driving with
the message and symbol displayed
may cause serious engine damage not
covered by the Mercedes-Benz Limited
Warranty.
Do not drive without sufficient amount
of coolant in the cooling system. The
engine will overheat, causing major en-
gine damage.
S203 MY03_A.book Page 265 Tuesday, January 28, 2003 2:22 PM
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266 Practical hintsWhat to do if …
During severe operating conditions and
stop-and-go city traffic, the coolant tem-
perature may rise close to 120°C.
Display
Possible cause
Suggested solution
Ï
COOLANT
STOP, ENGINE OFF!
The coolant is too hot.
Stop the vehicle and turn off the
engine.
Only start the engine again after
the message disappears. You could
otherwise damage the engine.
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.
Turn off the engine, get out of the vehicle
and do not stand near the vehicle until it
cools down.
!The engine should not be operated with
the coolant temperature above 248°F
(120°C). Doing so may cause serious
engine damage which is not covered by
the Mercedes-Benz Limited Warranty.
S203 MY03_A.book Page 266 Tuesday, January 28, 2003 2:22 PM
Page 261 of 370
267 Practical hints
What to do if …
Display
Possible cause
Suggested solution
Ï
COOLANT
STOP, ENGINE OFF!
The poly-V-belt could be broken.
Stop immediately and 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. No-
tify an authorized Mercedes-Benz
Center.
If it is intact:
Do not continue to drive the vehicle
with this message displayed. Doing
so could result in serious engine
damage that is not covered by the
Mercedes-Benz Limited Warranty.
COOLANT
VISIT WORKSHOP!
The cooling fan for the coolant is mal-
functioning.
Observe the coolant temperature
display.
Have the fan replaced as soon as
possible.
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270 Practical hintsWhat to do if …Display
Possible cause
Suggested solution
:
ENGINE OIL LEVEL
STOP, ENGINE OFF!
There is no oil in the engine. There is a
danger of engine damage.
Carefully bring the vehicle to a halt
as soon as possible.
Turn off the engine.
Add engine oil.
ENGINE OIL LEVEL
CHECK LEVEL!
The engine oil level is too low.
Check the engine oil level
(page 235) and add oil as re-
quired.
ENGINE OIL LEVEL
REDUCE OIL LEVEL!
You have added too much engine oil.
There is a risk of damaging the engine or
the catalytic converter.
Have oil siphoned. Observe all legal
requirements with respect to its
disposal.
ENGINE OIL
VISIT WORKSHOP!
The engine oil has dropped to a critical
level.
Check the engine oil level
(page 235) and add oil as re-
quired.
If you must add engine oil frequent-
ly, have the engine checked for
possible leaks.
There is water in the oil.
Have the oil checked.
ENGINE OIL LEVEL
VISIT WORKSHOP!
The measuring system is malfunctioning.
Have the measuring system
checked by an authorized
Mercedes-Benz Center.
S203 MY03_A.book Page 270 Tuesday, January 28, 2003 2:22 PM