Page 612 of 761

611 Practical hints
What to do if …?
ProblemPossible cause/consequenceSuggested solution
75
The front passenger front
air bag off indicator lamp
does not illuminate and/or
does not remain illuminat-
ed with the weight of a typ-
ical 12-month-old child in a
standard child restraint or
less on the front passen-
ger seat.
The system is malfunctioning.Make sure there is nothing between seat cushion and child seat and
check installation of the child seat.
Make sure no objects applying supplemental weight onto the seat
are present.
Make sure no objects which apply forces to the seat are present
(e.g. objects such as books, briefcases etc. lodged behind or around
the seat, head restraints pushing against roof etc.). The system may
recognize such forces as supplemental weight.
If the front passenger front air bag off indicator lamp remains out,
have the system checked as soon as possible by an authorized
Mercedes-Benz Center. Do not transport a child on the front pas-
senger seat until the system has been repaired.
Also read and observe any messages in the multifunction display
and follow corrective steps (
page 612).
Warning!G
If the59indicator lamp does
not illuminate or remains out with the
weight of a typical 12-month-old child in a
standard child restraint or less on the front
passenger seat, do not transport a child on
the front passenger seat until the system
has been repaired.
Page 613 of 761

612 Practical hints
What to do if …?
Vehicle status messages in the multi-
function display
Warning and malfunction messages ap-
pear in the multifunction display located in
the instrument cluster.
Certain warning and malfunction messag-
es are accompanied by an audible signal.
High-priority messages are shown in red
on the multifunction display. Messages of
lower priority are also shown in yellow or
white.
Address these messages accordingly and
follow the additional instructions given in
this Operator’s Manual.Certain messages of high priority cannot
be cleared from the multifunction display
using# or L on the multifunction
steering wheel (
page 265).
Other messages of high priority and mes-
sages of less immediate priority can be
cleared from the multifunction display
using# or L. They are then stored
in the vehicle status message memory
(
page 280). Remember that clearing a
message will only make the message dis-
appear. Clearing a message will not cor-
rect the condition that caused the
message to appear.
Warning!G
No messages will be displayed if either the
instrument cluster or the multifunction dis-
play is inoperative.
As a result, you will not be able to see infor-
mation about your driving conditions, such
as speed or outside temperature, warn-
ing/indicator lamps, malfunction/warning
messages or the failure of any systems.
Driving characteristics may be impaired.
If you must continue to drive, please do so
with added caution. Contact an authorized
Mercedes-Benz Center as soon as possible.
Page 614 of 761
613 Practical hints
What to do if …?
On the pages that follow, you will find a
compilation of the most important warning
and malfunction messages that may ap-
pear in the malfunction display.
For your convenience the messages are di-
vided into two sections:
Text messages (page 614)
Symbol messages (page 626)
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 condition noted may cause
damage not covered by the Mercedes-Benz
Limited Warranty, or result in property dam-
age or personal injury.
iSwitching on the ignition causes all instru-
ment cluster lamps (except high beam headlamp
indicator lamp and turn signal indicator lamps
unless activated) as well as the multifunction dis-
play to come on. Make sure the lamps and multi-
function display are in working order before
starting your journey.
Page 620 of 761

619 Practical hints
What to do if …?
Display Possible cause/consequencePossible solution
Front pass. airbag
disabled
See Oper. ManualWith the seat unoccupied and the ignition switched on (page 344),
the 59indicator lamp right of the instrument cluster should
illuminate and remain illuminated, indicating that the OCS (
page 47)
has deactivated the air bag.
the message “Front passenger airbag enabled See Oper. Manual” or the
message “Front passenger airbag disabled See Oper. Manual” should not
appear in the multifunction display at any time the seat is unoccupied.
Wait at least 60 seconds for the system to complete the necessary check
cycles and to make sure neither message appears in the multifunction dis-
play.
If above conditions are met, you can occupy the front passenger seat again.
Depending on the front passenger classification sensed by the OCS
(
page 47), the59indicator lamp will remain illuminated or go
out.
If above conditions are not met, the system is not working properly. Have the
system checked as soon as possible by an authorized Mercedes-Benz Center.
Warning!G
If the 59indicator lamp re-
mains illuminated with an adult occupant on
the front passenger seat even after
performing the above corrective steps, do
not have any passenger use the front pas-
senger seat until the system has been re-
paired.
Page 622 of 761

621 Practical hints
What to do if …?
Display Possible cause/consequencePossible solution
Front pass. airbag
enabled
See Oper. ManualWith the seat unoccupied and the ignition switched on (page 344),
the 59indicator lamp right of the instrument cluster should
illuminate and remain illuminated, indicating that the OCS (
page 47)
has deactivated the air bag.
the message “Front passenger airbag enabled See Oper. Manual” or the
message “Front passenger airbag disabled See Oper. Manual” should not
appear in the multifunction display at any time the seat is unoccupied.
Wait at last 60 seconds for the system to complete the necessary check
cycles and to make sure neither message appears in the multifunction dis-
play.
If above conditions are met, you can occupy the front passenger seat again.
Depending on the front passenger classification sensed by the OCS
(
page 47), the 59indicator lamp will remain illuminated or go
out.
If above conditions are not met, the system is not working properly. Have the
system checked as soon as possible by an authorized Mercedes-Benz Center.
Warning!G
If the 59indicator lamp re-
mains illuminated with an adult occupant on
the front passenger seat even after
performing the above corrective steps, do
not have any passenger use the front pas-
senger seat until the system has been re-
paired.
Page 624 of 761

623 Practical hints
What to do if …?
Display Possible cause/consequencePossible solution
PRE-SAFE
inoperative
See Oper. ManualPRE-SAFE® itself has failed. All other occu-
pant safety systems, such as the air bags,
are still available.Contact an authorized Mercedes-Benz Center as soon as pos-
sible.
Radar sensor
deactivated
See Oper. ManualYou attempt to activate DISTRONIC Plus*,
Park Assist* or PRE-SAFE® Brake* even
though you have switched off the radar sen-
sors* on the vehicle.
Check if the radar sensors* may be switched on (page 282).
Switch on the radar sensors* using the instrument cluster
control system.
Check tire pressures
and then restart
Run Flat Indicator
(Canada only)There was a warning message about a loss
in tire inflation pressure and the Run Flat In-
dicator has not been reactivated yet.Check and adjust tire inflation pressure as required
(
page 560).
Then reactivate the Run Flat Indicator (page 566).
Run Flat Indicator
inoperative
(Canada only)The Run Flat Indicator is malfunctioning.Contact an authorized Mercedes-Benz dealer as soon as pos-
sible.
Service X
dueService X must be carried out (page 582).Have the maintenance service carried out by an authorized
Mercedes-Benz Center.
Service X exceeded
by X days
by XXX mls (km)Service X must be carried within the next ...
or before you have driven ... miles (kilome-
ters) (
page 582).
Have the maintenance service carried out by an authorized
Mercedes-Benz Center as soon as possible.
Page 625 of 761

624 Practical hints
What to do if …?
Display Possible cause/consequencePossible solution
Shift to P or N
to start engineYou have attempted to start the engine
while the automatic transmission was set to
position R or D.Shift the automatic transmission to P or N (page 399).
Tire pressure
Check tiresThe pressure has fallen significantly in one
or more tires.Carefully bring the vehicle to a halt, avoiding abrupt steering
and braking maneuvers. Observe the traffic situation around
you.
Check and adjust tire inflation pressure as required
(
page 560).
If necessary, change the wheel (page 686).
Reactivate the Run Flat Indicator after adjusting the tire infla-
tion pressure values (
page 566).
Tire pressure monitor
inoperativeThe Advanced TPMS* or a wheel sensor is
malfunctioning.Have the Advanced TPMS* checked by an authorized
Mercedes-Benz Center.
Warning!G
Do not drive with a flat tire. A flat tire affects
the ability to steer or brake the vehicle. You
may lose control of the vehicle. Continued
driving with a flat tire will cause excessive
heat build-up and possibly a fire.
Page 631 of 761
630 Practical hints
What to do if …?
Display Possible cause/consequencePossible solution
Check brake
fluid levelThere is insufficient brake fluid in the reser-
voir.Risk of accident!
Carefully stop the vehicle in a safe location or
as soon as it is safe to do so.
Engage the electronic parking brake
(
page 395).
Contact an authorized Mercedes-Benz Cen-
ter.
Do not add brake fluid! This will not solve the
problem.
(USA only)
(Canada only)
Warning!G
Driving with the message “Check brake fluid
level ” displayed can result in an accident.
Have your brake system checked immedi-
ately. Do not add brake fluid before check-
ing the brake system. Overfilling the brake
fluid reservoir can result in spilling brake flu-
id 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.