2015 MERCEDES-BENZ S-Class Pre safe

Display messages
Possible causes/consequences and
M
MSolutions $(USA
only)J
(Canada
only)
Check Brake Fluid Check Brake Fluid
Level Level There is not enough brake fluid in the brake fluid reservoir.
In addition, the
$(USA only)/ J(Canada only) warning
lamp lights up in the instrument cluster and a warning tone
sounds.
G WARNING
The braking effect may be impaired.
There is a risk of an accident. X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions. Do not continue driving
under any circumstances.
X Secure the vehicle against rolling away (Y page 220).
X Consult a qualified specialist workshop.
X Do not add brake fluid. This does not correct the malfunction. #
Check Brake Pad Check Brake Pad
Wear Wear The brake pads/linings have reached their wear limit.
USA only: the red
$brake system warning lamp also lights up
while the engine is running.
X Visit a qualified specialist workshop. G
Inoperative Inoperative One or more main features of the mbrace system are malfunc-
tioning.
X Have the mbrace system checked immediately at a qualified
specialist workshop. PRE-SAFE Inopera‐ PRE-SAFE Inopera‐
tive See Opera‐ tive See Opera‐
tor's Manual tor's Manual
Important functions of PRE-SAFE
®
have failed. All other occupant
safety systems, e.g. air bags, remain available.
X Visit a qualified specialist workshop immediately. 324
Display
messagesOn-board computer and displays

Display messages
Possible causes/consequences and
M
MSolutions Collision Preven‐
Collision Preven‐
tion Assist Plus tion Assist Plus
Currently Unavail‐ Currently Unavail‐
able See Opera‐ able See Opera‐
tor's Manual tor's Manual COLLISION PREVENTION ASSIST PLUS is temporarily not opera-
tional. Possible causes are:
R the radar sensor system is temporarily inoperative, e.g. due to
electromagnetic radiation emitted by nearby TV or radio sta-
tions or other sources of electromagnetic radiation.
R the system is outside the operating temperature range.
R the on-board voltage is too low.
When the causes stated above no longer apply, the display mes-
sage disappears.
COLLISION PREVENTION ASSIST PLUS is operational again.
If the display message does not disappear:
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 220).
X Restart the engine. Collision Preven‐ Collision Preven‐
tion Assist Plus tion Assist Plus
Inoperative Inoperative COLLISION PREVENTION ASSIST PLUS is temporarily inoperative
due to a malfunction. Adaptive Brake Assist may also have failed.
X Visit a qualified specialist workshop. PRE-SAFE
PRE-SAFE
Functions
Functions
Currently Limited
Currently Limited
See See Operator's
Operator's Man‐
Man‐
ual
ual PRE
‑SAFE ®
PLUS or PRE ‑SAFE®
Brake is temporarily inoperative.
Possible causes are:
R function is impaired due to heavy rain or snow.
R the radar sensor system is temporarily inoperative, e.g. due to
electromagnetic radiation emitted by nearby TV or radio sta-
tions or other sources of electromagnetic radiation.
R the system is outside the operating temperature range.
R the on-board voltage is too low.
When the causes stated above no longer apply, the display mes-
sage disappears.
PRE ‑SAFE ®
PLUS and PRE ‑SAFE®
Brake are operational again.
If the display message does not disappear:
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 220).
X Restart the engine. PRE-SAFE PRE-SAFE
Functions
Functions
Limited See Opera‐
Limited See Opera‐
tor's Manual tor's Manual PRE
‑SAFE ®
PLUS or PRE‑ SAFE®
Brake is unavailable due to a mal-
function. BAS PLUS may also have failed.
X Visit a qualified specialist workshop. Display
messages
325On-board computer and displays Z

Display messages
Possible causes/consequences and
M
MSolutions Radar Sensors
Radar Sensors
Dirty See Opera‐ Dirty See Opera‐
tor's Manual tor's Manual At least one of the following driving systems or driving safety sys-
tems is temporarily restricted or inoperative:
R PRE-SAFE ®
PLUS
R PRE-SAFE ®
Brake
R COLLISION PREVENTION ASSIST PLUS
R Active Lane Keeping Assist
R Active Blind Spot Assist
R DISTRONIC PLUS with Steering Assist and Stop&Go Pilot
Possible causes are:
R the sensors in the radiator trim and/or in the bumpers are dirty.
R the function of the driving system and/or driving safety system
is impaired due to heavy rain or snow.
A warning tone also sounds.
When the causes stated above no longer apply, the display mes-
sage disappears. All driving systems/driving safety systems are
operative again.
If the display message does not disappear:
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 220).
X Switch off the engine.
X Clean the sensors in the following locations (Y page 415):
R in the radiator trim
R in the front bumper
R in the rear bumper, particularly in the middle of the rear
bumper
X Restart the engine.
The display message disappears. 326
Display
messagesOn-board computer and displays

Display messages
Possible causes/consequences and
M
MSolutions Check Left Rear
Check Left Rear
Belt See Opera‐ Belt See Opera‐
tor's Manual tor's Manual
or
Check Right Rear
Check Right Rear
Belt See Opera‐ Belt See Opera‐
tor's Manual tor's Manual The seat belt buckle extender on the right or left of the rear com-
partment is not in the predefined position. The belt strap may be
jammed in the belt tongue.
G WARNING
If the seat belt buckle extender is not in the predefined position,
the seat belt cannot provide the intended level of protection.
There is an increased risk of injury. X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Release the jamming.
X Repeat the seat belt fastening procedure. The seat belt buckle extender on the right or left of the rear com-
partment is not in the predefined position. The seat belt buckle
extender may be jammed.
G WARNING
If the seat belt buckle extender is not in the predefined position,
the seat belt cannot provide the intended level of protection.
There is an increased risk of injury. X Move the seat cushion forwards (Y page 123) and remove the
cause of the jamming.
X Repeat the seat belt fastening procedure. The seat belt buckle extender on the right or left of the rear com-
partment is not in the predefined position. The seat belt may be
locked.
G WARNING
If the seat belt buckle extender is not in the predefined position,
the seat belt cannot provide the intended level of protection.
There is an increased risk of injury. X Completely take off your seat belt.
X Repeat the seat belt fastening procedure. Display
messages
327On-board computer and displays Z

Display messages
Possible causes/consequences and
M
MSolutions 6
Rear Left Malfunc‐ Rear Left Malfunc‐
tion Service tion Service
Required Required
orRear
Rear
Right Malfunction
Right Malfunction
Service Required Service Required The restraint system has malfunctioned at the rear on the left or
right. The 6warning lamp also lights up in the instrument clus-
ter.
G WARNING
The air bags or Emergency Tensioning Devices may either be trig- gered unintentionally or, in the event of an accident, may not be
triggered.
There is an increased risk of injury.
X Visit a qualified specialist workshop. 6
Rear Left Malfunc‐ Rear Left Malfunc‐
tion Service tion Service
Required Required
orRear
Rear
Right Malfunction
Right Malfunction
Service Required Service Required G
WARNING
If the seat belt buckle extender is not in the predefined position,
the seat belt cannot provide the intended level of protection.
There is an increased risk of injury. X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Perform the specified assistance measures when display mes-
sage Check Left Rear Belt See Operator's Manual Check Left Rear Belt See Operator's Manual or
Check
Check Right
RightRear
RearBelt
Belt See
SeeOperator's
Operator's Manual
Manualis shown
(Y page 327).
If the display message does not disappear:
X Visit a qualified specialist workshop immediately. 6
Rear Center Mal‐ Rear Center Mal‐
function Service function Service
Required Required The restraint system has malfunctioned at the rear center. The
6 warning lamp also lights up in the instrument cluster.
G WARNING
The air bags or Emergency Tensioning Devices may either be trig- gered unintentionally or, in the event of an accident, may not be
triggered.
There is an increased risk of injury.
X Visit a qualified specialist workshop. Display
messages
329On-board computer and displays Z

Display messages
Possible causes/consequences and
M
MSolutions Front Passenger
Front Passenger
Airbag Disabled Airbag Disabled
See See
Operator's
Operator's Man‐
Man‐
ual
ual The front-passenger air bag is deactivated during the journey, even
though:
R an adult
or
R a person of the corresponding stature is on the front-passenger
seat
If additional forces are applied to the seat, the system may inter-
pret the occupant's weight as lower than it actually is.
G WARNING
The front-passenger air bag does not deploy during an accident.
There is an increased risk of injury. X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 220).
X Switch the ignition off.
X Have the occupant get out of the vehicle.
X Keep the seat unoccupied, close the front-passenger door and
switch on the ignition.
X Observe the PASSENGER AIR BAG indicator lamps in the center
console and the multifunction display and check the following:
Seat unoccupied and ignition switched on:
R the PASSENGER AIR BAG OFF and PASSENGER AIR BAG ON
indicator lamps must light up simultaneously for approx-
imately six seconds.
R the PASSENGER AIR BAG OFF indicator lamp must then light
up and remain lit. If the indicator lamp is on, OCS has disabled the front-passenger air bag (Y page 60).
R the display messages Front FrontPassenger
Passenger Airbag
AirbagEnabled
Enabled
See Operator's Manual
See Operator's Manual orFront Passenger Airbag
Front Passenger Airbag
Disabled
Disabled See
SeeOperator's
Operator's Manual
Manualmust not appear in the
multifunction display.
X Wait for a period of at least 60 seconds until the necessary sys-
tem checks have been completed.
X Make sure that the display messages do not appear in the mul-
tifunction display.
If these conditions are fulfilled, the front-passenger seat can be
occupied again. Whether the PASSENGER AIR BAG OFF or ON
indicator lamp remains lit or goes out depends on how OCS clas- sifies the occupant.
If the conditions are not fulfilled, the system is not operating cor-
rectly. Display
messages
331On-board computer and displays Z

Display messages
Possible causes/consequences and
M
MSolutions X
Visit a qualified specialist workshop immediately.
For further information about the Occupant Classification System, see (Y page 60). Front Passenger
Front Passenger
Airbag Airbag
Enabled
Enabled See
See
Operator's Manual
Operator's Manual The front-passenger air bag is enabled during the journey, even
though:
R a child, a small adult or an object weighing less than the sys-
tem's weight threshold is located on the front-passenger seat
or
R the front-passenger seat is unoccupied
The system may detect objects or forces applying additional
weight on the seat.
G WARNING
The air bag may deploy unintentionally.
There is an increased risk of injury. X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 220).
X Switch the ignition off.
X Open the front-passenger door.
X Remove the child and the child restraint system from the front-
passenger seat.
X Make sure that there are no objects on the seat adding to the
weight.
The system may otherwise detect the additional weight and
interpret the seat occupant's weight as greater than it actually
is.
X Keep the seat unoccupied, close the front-passenger door and
switch on the ignition.
X Observe the PASSENGER AIR BAG indicator lamps in the center
console and the multifunction display and check the following:
Seat unoccupied and ignition switched on:
R the PASSENGER AIR BAG OFF and PASSENGER AIR BAG ON
indicator lamps must light up simultaneously for approx-
imately six seconds.
R the PASSENGER AIR BAG OFF indicator lamp must then light
up and remain lit. If the indicator lamp is on, OCS (Occupant
Classification System) has deactivated the front-passenger
air bag (Y page 60).
R the display messages Front FrontPassenger
Passenger Airbag
AirbagEnabled
Enabled
See Operator's Manual
See Operator's Manual orFront Passenger Airbag
Front Passenger Airbag 332
Display
messagesOn-board computer and displays

Display messages
Possible causes/consequences and
M
MSolutions 4
Engine Oil Level Engine Oil Level
Low Stop Vehicle Low Stop Vehicle
Turn Engine Off Turn Engine Off The engine oil level is too low. There is a risk of engine damage.
X Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 220).
X Check the engine oil level (Y page 405).
X If necessary, add engine oil (Y page 407).8
Fuel Level Low Fuel Level Low The fuel level has dropped into the reserve range.
X Refuel at the nearest gas station. C
C There is only a very small amount of fuel in the fuel tank.
X Refuel at the nearest gas station without fail. 8
Gas Cap Loose Gas Cap Loose The fuel system pressure is too low. The fuel filler cap is not closed
correctly or the fuel system is leaking.
X Check that the fuel filler cap is correctly closed.
If the fuel filler cap is not correctly closed: X Close the fuel filler cap.
If the fuel filler cap is correctly closed: X Visit a qualified specialist workshop. Display
messages
339On-board computer and displays Z