Page 278 of 394
278 Practical hintsWhat to do if …?Problem
Possible cause
Suggested solution
1
The red SRS indicator lamp lights
up while driving.
There is a malfunction in the restraint sys-
tems. The airbags or emergency tensioning
device (ETD) could deploy unexpectedly or
fail to activate in an accident.
Drive with added caution to the near-
est authorized Mercedes-Benz Cen-
ter.
Warning!
G
In the event that a malfunction of the SRS is
indicated as outlined above, the SRS may
not be operational. For your safety, we
strongly recommend that you visit an autho-
rized Mercedes-Benz Center immediately to
have the system checked; otherwise the
SRS may not be activated when needed in
an accident, which could result in serious or
fatal injury, or it might deploy unexpectedly
and unnecessarily, which could result in an
accident and/or injury to you or to others.
Page 279 of 394

279 Practical hints
What to do if …?
Problem
Possible cause
Suggested solution
;
(except Canada)
3
(Canada only)
You are driving with the parking brake set.
Release the parking brake
(page 45).
The red brake warning lamp
lights up while driving and you
hear a warning sound.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
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.
Page 280 of 394

280 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 impact emissions
Such malfunctions may result in excessive
emissions values and may switch the engine
to its Limp-Home Mode (emergency opera-
tion).
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 system.
It allows the accurate identification of
system malfunctions through the read-
out of diagnostic trouble codes. It is lo-
cated in the front left area of the
footwell next to the parking brake pedal.
The fuel cap is not closed tightly.
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.
A
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 251).
Page 281 of 394

281 Practical hints
What to do if …?
Problem
Possible cause
Suggested solution
•
The red coolant warning lamp
lights up when the engine is run-
ning.
There is insufficient coolant in the reservoir.
Add coolant to prevent engine from
overheating (
page 256).
If this warning lamp lights up 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
lights up 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 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.
Page 283 of 394

283 Practical hints
What to do if …?
Messages in the display
The control system shows warning and
malfunction messages in the multifunction
display.
Certain warning and malfunction messag-
es are accompanied by an audible signal.
Address these messages accordingly and
follow the additional instructions given in
this Operator’s Manual.
Selecting the malfunction memory menu in
the control system (
page 122) displays
both cleared and uncleared messages.
High-priority messages appear in the mul-
tifunction display in red color.
Certain messages of high priority cannot
be cleared from the multifunction display
using the reset knob (page 111).
Other high priority messages and messag-
es of less immediate priority (regular dis-
play colors) can be cleared from the
multifunction display using the reset knob
and are then stored in the malfunction
message memory (
page 122).On the pages that follow, you will find a
compilation of all the messages that may
appear in the display. High priority mes-
sages appear on a red background.
Warning!
G
All categories of messages contain impor-
tant information which should be taken note
of and, where a malfunction is indicated, ad-
dressed as soon as possible at an autho-
rized Mercedes-Benz Center.
Failure to repair the condition noted may
cause damage not covered by the
Mercedes-Benz Limited Warranty, or result
in property damage or personal injury.Warning!
G
No messages will be displayed if either the
instrument cluster or the multifunction dis-
play is inoperative.
Contact your nearest authorized
Mercedes-Benz Center.
iTurning the key in starter switch to
position2, or pressing the KEY-
LESS-GO* start/stop button (if so
equipped) twice to position2 causes
all lamps as well as the multifunction
display to come on. Ensure that they
are all in working order before starting
your journey.
Page 285 of 394

285 Practical hints
What to do if …?
Display
Possible cause
Suggested solution
ABS
Anti-lock
braking system
not working!
The charging voltage has fallen below
10 volts and the ABS has switched off.
The brake system is still functioning nor-
mally but without the ABS available.
When the voltage is above this value
again, the ABS is operational again.
Continue driving with added caution.
Wheels will lock during hard braking,
reducing steering capability.
Have the system checked at an autho-
rized Mercedes-Benz Center as soon
as possible.
Failure to follow these instructions in-
creases the risk of accident.
BAS
not available
See operator’s manual
The charging voltage has fallen below
10 volts and the BAS has switched off.
The brake system is still functioning nor-
mally but without the BAS available.
When the voltage is above this value
again, the BAS is operational again.
Have the system checked at an autho-
rized Mercedes-Benz Center if you see
the warning message for a longer peri-
od of time.
Failure to follow these instructions in-
creases the risk of accident.
Page 287 of 394
287 Practical hints
What to do if …?
Display
Possible cause
Suggested solution
;
(USA only)
3
(Canada only)
Brake fluid
Visit workshop
There is insufficient brake fluid in the res-
ervoir.
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.
Page 289 of 394

289 Practical hints
What to do if …?
Display
Possible cause
Suggested solution
F
Key
do not forget key
This display appears (for a maximum of
60 seconds) if the driver’s door is opened
with the engine shut off and no key in the
starter switch.
Message is only a reminder.
Insert key in the starter switch.
Take the SmartKey with KEY-
LESS-GO* with you when leaving the
vehicle.
B
Coolant
Check level
The coolant level is too low.
Add coolant (
page 256).
If you have to add coolant frequently,
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.