Page 380 of 506
378 Practical hintsWhat to do if …Symbol messagesDisplay symbol
Display messages
Possible cause
Possible solution
#
Undervoltage
Switch off
consumers
The battery has insufficient voltage.
Turn off unnecessary electrical con-
sumers.
Visit workshop
The battery is no longer charging.
Possible causes:
alternator malfunctioning
broken poly-V-belt
Do not forget that the brake system re-
quires electrical energy and may be oper-
ating with restricted capability.
Considerably greater brake pedal force is
required and the stopping distance is in-
creased.
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. Ad-
just driving to be consistent with
reduced braking responsiveness.
Page 381 of 506
379 Practical hints
What to do if …
Display symbol
Display messages
Possible cause
Possible solution
#
Battery/Alternator
Stop vehicle
The battery is malfunctioning.
The SBC brake system requires electrical
energy and therefore has only limited op-
eration. Considerably greater brake pedal
force is required and the stopping dis-
tance is increased.
Stop the vehicle as soon as it is safe
to do so. Adjust driving to be consis-
tent with reduced braking responsive-
ness.
Notify an authorized Mercedes-Benz
Center.
Low voltage
Start engine
The battery has insufficient voltage.
Start the engine (
page 46).
Malfunction
Electrical consumers
switched off
The consumer battery has insufficient
voltage and can no longer supply the con-
venience functions such as seat ventila-
tion*.
The electrical consumers will come back
online as soon as on-board voltage is suf-
ficient.
(
Backrest, right rear
not locked
The rear seat backrest is not engaged.
Adjust the rear seat backrest until it is
fully engaged in position.
Backrest, left rear
not locked
The rear seat backrest is not engaged.
Adjust the rear seat backrest until it is
fully engaged in position.
Page 382 of 506
380 Practical hintsWhat to do if …Display symbol
Display messages
Possible cause
Possible solution
2
Brake wear
Visit workshop
The brake pads have reached their wear
limit.
Brake pad thickness must be visually
inspected at the intervals specified in
the Maintenance Booklet.
Have the brake pads replaced as soon
as possible.
T
Reduced braking power
Depress brake
pedal fully
The SBC brake system is in emergency
operation mode. Considerably greater
brake pedal force is required and the
stopping distance is increased.
The maximum speed is limited to 55 mph
(90 km / h).
Do not drive any further.
Stop the vehicle and notify an autho-
rized Mercedes-Benz Center.
Prevent the vehicle from rolling away
by blocking the wheels with wheel
chocks or other sizable objects.
Call for Roadside Assistance.
(USA only);(Canada only)3
Reduced braking power
Start engine
The battery has insufficient voltage and
cannot supply sufficient power to the
SBC brake system.
Start the engine.
The message disappears when suffi-
cient voltage is available.
Page 383 of 506
381 Practical hints
What to do if …
Display symbol
Display messages
Possible cause
Possible solution
(USA only);(Canada only)3
Reduced braking power
Visit workshop
The SBC brake system is in emergency
operation mode. Considerable brake ped-
al force is required and the stopping dis-
tance is increased.
Continue driving with added caution.
Adjust driving to be consistent with
reduced braking responsiveness.
Visit an authorized Mercedes-Benz
Center as soon as possible.
Service brake
Visit workshop
There are malfunctions, but the SBC
brake system is operating normally.
Visit an authorized Mercedes-Benz
Center as soon as possible.
Brake overheated
Drive carefully
The brake system is overheated due to an
excessive load on the brakes.
Relieve the load on the brake system.
Drive more smoothly and think ahead
to avoid unnecessary braking.
When driving down slopes, shift into a
lower gear to use the engine’s braking
power (
page 176).
Cautiously continue driving so that
the air stream will cool down the
brakes.
Release
parking brake
You are driving with the parking brake
set.
Release the parking brake
(page 48).
Page 384 of 506
382 Practical hintsWhat to do if …Display symbol
Display messages
Possible cause
Possible solution
(USA only);(Canada only)3
Brake fluid
Visit workshop
There is insufficient brake fluid in the
reservoir.
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 while these messages are displayed
can result in an accident. Have your brake
system checked immediately.
If there is a malfunction in the SBC brake
system, we recommend that the vehicle be
transported with all wheels off the ground
using flatbed or appropriate wheel lift/dolly
equipment.
A tow bar must be used if circumstances do
not permit the use of the recommended
towing methods and the vehicle requires
towing with all four wheels on the ground.
Towing the vehicle with all four wheels on
the ground is only permissible for distances
u p t o 3 0 m i l e s ( 5 0 k m ) a n d a t a s p e e d n o t t o
exceed 30 mph (50 km / h). For more infor-
mation, refer to “Towing the vehicle”
(page 439).
If the SBC brake system enters its emergen-
cy operation mode, the driver must apply
significantly greater brake pedal pressure
and depress the pedal much further than
normal to obtain braking effect. If neces-
sary, apply full pressure to the brake pedal.
Brakes may only be applied to the front
wheels. Stopping distance is increased!
Do not add brake fluid before checking the
brake system. Overfilling the brake fluid res-
ervoir 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.!Brake pad thickness must be visually
inspected by a qualified technician at
the intervals specified in the
Maintenance Booklet.
Page 385 of 506
383 Practical hints
What to do if …
Display symbol
Display messages
Possible cause
Possible solution
?
(USA only)
±
(Canada only)
Visit workshop
There may be a malfunction in the:
fuel injection system
ignition system
exhaust system
fuel system
Have the measuring system checked
by an authorized Mercedes-Benz Cen-
ter.
B
Coolant
Check level
The coolant level is too low.
Add coolant (
page 308).
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.
Page 386 of 506
384 Practical hintsWhat 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 symbol
Display messages
Possible cause
Possible solution
Ï
Coolant
Stop, engine off
The coolant is too hot.
Stop the vehicle.
Only start the engine again after the
message disappears. You could other-
wise 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 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.
Page 387 of 506
385 Practical hints
What to do if …
Display symbol
Display messages
Possible cause
Possible 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 in-
operative water pump which may re-
sult in damage to the engine. Notify
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 Warranty.
Drive immediately to the nearest au-
thorized Mercedes-Benz Center.
Coolant
Visit workshop
The cooling fan for the coolant is malfunc-
tioning.
Observe the coolant temperature dis-
play.
Have the fan replaced as soon as pos-
sible.
