Page 98 of 489

97 Safety and Security
Driving safety systems
Notes on driving with the 
electro-hydraulic brake system
Following extended periods of only 
minor loads to your brake system, you 
should occasionally apply the brakes 
when traveling at high speeds. This 
improves the grip of the brake pads. 
After driving on wet or snow-covered 
roads, you should apply your brakes 
firmly before parking your vehicle. 
This produces heat which serves to 
dry the brake disks and help prevent 
corrosion. 
On long and steep grades, shift to a 
lower gear (gear range1, 2, or 3) to 
prevent the brakes from overheating 
and to reduce brake wear.
After hard braking, it is advisable to 
drive on for some time so that the air 
stream will cool down the brakes 
faster. 
Only Mercedes-Benz approved compo-
nents (e.g. brake pads) should be in-
stalled on your vehicle. Brake pads 
not approved by Mercedes-Benz may 
impair the safety of your vehicle.
Warning!G
Be very careful not to endanger other road 
users when you apply the brakes.  
     
        
        Page 269 of 489

268 Operation
Driving instructions
Power assistanceBrakes
Warning!G
The brake system requires electrical energy 
for operation.
A malfunction in the vehicle’s power supply 
or electrical system may impair brake sys-
tem operation and switch it into its emer-
gency operation mode. In such a case, the 
red brake warning lamp (
page 345) and 
warning messages (
page 359) in the in-
strument cluster come on while driving. To 
brake, the driver must then apply signifi-
cantly greater brake pedal pressure and de-
press the pedal much further to obtain the 
expected braking effect. If necessary, apply 
full pressure to the brake pedal. Brakes are 
only applied to the front wheels. Stopping 
distance is increased! If there is a malfunc-
tion in the electro-hydraulic brake system, 
we recommend that the vehicle be trans-
ported with all wheels off the ground using 
flatbed or appropriate wheel lift/dolly equip-
ment. 
 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 
up to 30 miles (50 km) and at a speed not to 
exceed 30 mph (50 km/h). For more infor-
mation, see “Towing the vehicle” 
(
page 434).
With the engine not running, there is no 
power assistance for the brake and steering 
systems. In this case, it is important to keep 
in mind that a considerably higher degree of 
effort is necessary to brake and steer the 
vehicle.
Warning!G
After driving in heavy rain for some time 
without applying the brakes or through wa-
ter deep enough to wet brake components, 
the first braking action may be somewhat 
reduced and increased pedal pressure may 
be necessary to obtain expected braking 
effect. Maintain a safe distance from 
vehicles in front.
Resting your foot on the brake pedal will 
cause excessive and premature wear of the 
brake pads.
It can also result in the brakes overheating 
thereby significantly reducing their effec-
tiveness. It may not be possible to stop the 
vehicle in sufficient time to avoid an 
accident. 
     
        
        Page 270 of 489

269 Operation
Driving instructions
To help prevent brake disk corrosion after 
driving on wet road surfaces (particularly 
salted roads), it is advisable to brake the 
vehicle with considerable force prior to 
parking. The heat generated serves to dry 
the brakes.
If your brake system is normally only 
subjected to moderate loads, you should 
occasionally test the effectiveness of the 
brakes by applying above-normal braking 
pressure at higher speeds. This will also 
enhance the grip of the brake pads.Refer to the description of the Brake Assist 
System (BAS) (page 91).
Brake pad wear or a leak in the system may 
be the reason for low brake fluid in the 
reservoir.
The brake fluid level in the reservoir may 
be too low or the electro-hydraulic brake 
system may be malfunctioning if the brake 
warning lamp in the instrument cluster 
comes on and an acoustic warning sounds 
although the parking brake is released 
(
page 345). 
Observe additional messages in the 
multifunction display that may appear, see 
(
page 377) through (page 382).
Have the brake system inspected immedi-
ately. Contact an authorized 
Mercedes-Benz Center.All checks and service work on the brake 
system should be carried out by qualified 
technicians only. Contact an authorized 
Mercedes-Benz Center.
Only install brake pads and brake fluid 
recommended by Mercedes-Benz.
!Because the ESP® operates automatically, 
the engine must be shut off (SmartKey in starter 
switch position 0 or 1or KEYLESS-GO* 
start/stop button in position 0 or 1) when the 
parking brake is being tested on a brake test 
dynamometer.
Active braking action through the ESP
® may 
otherwise seriously damage the brake system.
Warning!G
Make sure not to endanger any other road 
users when carrying out these braking 
maneuvers. 
Warning!G
If other than recommended brake pads are 
installed, or other than recommended brake 
fluid is used, the braking properties of the 
vehicle can be degraded to an extent that 
safe braking is substantially impaired. This 
could result in an accident.
Be certain to read and observe the warning 
notices on brake pad replacement 
(
page 96).
!When driving down long and steep grades, 
relieve the load on the brakes by shifting into a 
lower gear to use the engine’s braking power. 
This helps prevent overheating of the brakes and 
reduces brake pad wear. 
     
        
        Page 349 of 489
348 Practical hints
What to do if …
ProblemPossible cause/consequenceSuggested solution
DThe red coolant warning lamp 
comes on when the engine is 
running.There is insufficient coolant in the reservoir.
If this warning lamp comes on frequently, 
there is a leak in the cooling system.
If the coolant level is correct, the electric ra-
diator fan may be broken. Immediately add coolant to prevent 
engine from overheating 
(
page 288).
Have the cooling system checked.
If the coolant temperature is below 
248°F (120°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.
DThe red coolant warning lamp 
comes on when the engine is 
running and you hear a warning 
sound.The coolant temperature has exceeded 
248°F (120°C).Stop in a safe location as soon as pos-
sible and allow the engine and coolant 
to cool down.