2013 MERCEDES-BENZ SL-CLASS ROADSTER ECU

Display messages Possible causes/consequences and
M SolutionsX
Wait for a period of at least 60 seconds until the necessary
system checks have been completed.
X Make sure that the display messages do not appear in the
multifunction display.
If these conditions are fulfilled, the front-passenger seat can be
occupied again.
Whether the ^a indicator lamp remains lit
or goes out depends on how OCS classifies the occupant.
If the conditions are not fulfilled, the system is not operating
correctly.
X Visit a qualified specialist workshop immediately.
For further information about the Occupant Classification System,
see ( Y page 43). Front Passenger
Airbag Disabled
See Operator's
Manual The front-passenger air bag and front-passenger knee bag are
deactivated during the journey, although:
R
an adult
or
R a person larger than a certain size is occupying the front-
passenger seat.
If additional forces are applied to the seat, the system may
interpret the occupant's weight as lower than it actually is.
G WARNING
The front-passenger front air bag and front passenger knee bag
may not be triggered in the event of 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 154).
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 ^a indicator
lamp in the center console and
the multifunction display and check the following:
Seat unoccupied and ignition switched on:
R the ^a indicator

lamp must light up and remain lit. When
the indicator lamp is on, OCS has disabled the front-passenger
air bag and front-passenger knee bag ( Y page 43).
R the Front Passenger Airbag Enabled See Operator's
Manual or Front Passenger Airbag Disabled See 234
Display messages
On-board computer and displays

Display messages Possible causes/consequences and
M Solutions?
Coolant Too Hot
Stop Vehicle Turn
Engine Off The coolant is too hot.
A warning tone also sounds.
G WARNING
Do not drive when your engine is overheated. This can cause some
fluids which may have leaked into the engine compartment to
catch fire.
Steam from the overheated engine can also cause serious burns
which can occur just by opening the hood.
There is a risk of injury.
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 154).
X Leave the vehicle and keep a safe distance from the vehicle until
the engine has cooled down.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by snow, slush or ice.
X Do not start the engine again until the display message goes out
and the coolant temperature is under 248 ‡ (120 †).
Otherwise, the engine could be damaged.
X Pay attention to the coolant temperature display.
X If the temperature increases again, visit a qualified specialist
workshop immediately.
Under
normal operating conditions and with the specified coolant
level, the coolant temperature may rise to 248 ‡
(120 †). Display messages
239
On-board computer and displays Z

Display messages Possible causes/consequences and
M Solutions# The battery is not being charged.
A warning tone also sounds.
Possible causes are:
R
a defective alternator
R a torn poly-V-belt
R a malfunction in the electronics
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 154).
X Open the hood.
X Check whether the poly-V-belt is torn.
If the poly-V-belt is torn:
! Do not
continue driving. The engine could otherwise overheat.
X Consult a qualified specialist workshop.
If the poly-V-belt is not damaged:
X Visit a qualified specialist workshop. 4
Check Engine Oil
At Next Refueling The engine oil level has dropped to the minimum level.
A warning tone also sounds.
X
Check the oil level when next refueling, at the latest
(Y page 497).
X If necessary, add engine oil ( Y page 498).
X Have the engine checked at a qualified specialist workshop if
engine oil needs to be added more often than usual.
! Avoid long journeys with too little engine oil. The engine will
otherwise be damaged.
Information on approved engine oils can be obtained from any
qualified specialist workshop or on the Internet at http://
www.mbusa.com (USA only). 8
Fuel Level Low The fuel level has dropped into the reserve range.
X
Refuel at the nearest gas station.240
Display messages
On-board computer and displays

Display messages Possible causes/consequences and
M SolutionsC 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 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. Driving systems
Display messages Possible causes/consequences and
M SolutionsABC
Malfunction The ABC function (Active Body Control) is restricted.
G WARNING
The vehicle's suspension tuning characteristics may be affected.
There is a risk of an accident.
X Do not drive at speeds above 50 mph (80 km/h).
X Visit a qualified specialist workshop. ABC
Malfunction Stop
Vehicle The vehicle level of the ABC is too low.
X
Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
After a
few seconds, the vehicle level is adjusted and the display
message disappears. The vehicle is leaking oil.
The display message is shown continuously.
G WARNING
The vehicle's suspension tuning characteristics may be affected.
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 154).
X Notify a qualified specialist workshop or breakdown service. Display messages
241
On-board computer and displays Z

Display messages Possible causes/consequences and
M SolutionsAct. Lane Keep.
Assist Currently
Unavailable See
Operator's Manual Active Lane Keeping Assist is deactivated and temporarily
inoperative. Possible causes are:
R
the windshield in the camera's field of vision is dirty.
R visibility is impaired due to heavy rain, snow or fog.
R there are no lane markings for a longer period.
R the lane
markings are worn, dark or covered, e.g. by dirt or snow.
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 154).
X Clean the windshield.
If the system detects that the camera is fully operational, the
display message disappears.
Lane Keeping Assist or Active Lane Keeping Assist is operational
again. Act. Lane Keep.
Assist Inoperative Active Lane Keeping Assist is defective.
X
Visit a qualified specialist workshop. Active Blind Spot
Assist Currently
Unavailable See
Operator's Manual Active Blind Spot Assist is temporarily inoperative. Possible
causes are:
R
the sensors are dirty.
R function is impaired due to heavy rain or snow.
R the radar sensor system is outside the operating temperature
range.
R the radar sensor system is temporarily inoperative, e.g. due to
electromagnetic radiation emitted by nearby TV or radio
stations or other sources of electromagnetic radiation.
The yellow 9 indicator lamps also light up in the exterior
mirrors.
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 154).
X Clean the sensors ( Y page 504).
X Restart the engine.
If the system detects that the sensors are fully operational, the
display message disappears.
Active Blind Spot Assist is operational again. Display messages
243
On-board computer and displays Z

Display messages Possible causes/consequences and
M SolutionsDISTRONIC PLUS
Currently
Unavailable See
Operator's Manual DISTRONIC is deactivated and temporarily inoperative. Possible
causes are:
R
the DISTRONIC PLUS cover in the radiator trim is dirty
R function is impaired due to heavy rain or snow.
R the sensors in the bumpers are dirty.
R the radar sensor system is temporarily inoperative, e.g. due to
electromagnetic radiation emitted by nearby TV or radio
stations or other sources of electromagnetic radiation.
R the system is outside the operating temperature range.
R the on-board voltage is too low.
A warning tone also sounds.
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 154).
X Clean the DISTRONIC PLUS cover in the radiator trim and the
bumper ( Y page 504).
X Restart the engine.
If the system detects that the sensors are fully operational, the
display message disappears.
DISTRONIC is operational again. DISTRONIC PLUS
Inoperative DISTRONIC PLUS is defective.
BAS PLUS (Brake Assist PLUS) and PRE-SAFE
®
Brake may be
inoperative as well.
A warning tone also sounds.
X Visit a qualified specialist workshop. DISTRONIC PLUS
Passive You have depressed the accelerator pedal. DISTRONIC PLUS is no
longer controlling the speed of the vehicle.
X
Remove your foot from the accelerator pedal. DISTRONIC PLUS
--- mph An activation condition for DISTRONIC PLUS is not fulfilled.
X
Check the activation conditions for DISTRONIC PLUS
(Y page 164). Display messages
245On-board computer and displays Z

Tires
Display messages Possible causes/consequences and
M Solutions
Check
Tire Pressure The tire pressure loss warning system has detected a significant
loss in pressure.
A warning tone also sounds.
G WARNING
With tire pressures which are too low, there is a risk of the
following hazards:
R they may burst, especially as the load and vehicle speed
increase.
R they may

wear excessively and/or unevenly, which may greatly
impair tire traction.
R the driving characteristics, as well as steering and braking, may
be greatly impaired.
There is a risk of an accident.
X Stop the vehicle without making any sudden steering or braking
maneuvers. Pay

attention to the traffic conditions as you do so.
X Secure the vehicle against rolling away ( Y page 154).
X If there is a flat tire, inspect the tires ( Y page 509).
X Check the tire pressures and, if necessary, correct the tire
pressure.
X Restart the tire pressure loss warning system when the tire
pressure is correct (Y page 533). Check
Tire Pressure
Then Restart Run
Flat Indicator The tire pressure loss warning system generated a display
message and has not been restarted since.
X
Set the correct tire pressure in all four tires.
X Restart the tire pressure loss warning system ( Y page 533).
Run Flat Indicator
Inoperative The tire pressure loss warning system is faulty.
X
Visit a qualified specialist workshop. Tire pressure
will be displayed
after driving a
few minutes The tire pressure monitor is measuring the tire pressure.
X
Drive on.
The tire

pressures appear in the multifunction display after you
have been driving for a few minutes. Tire
Press. Monitor
Inoperative The tire pressure monitor is faulty.
X
Visit a qualified specialist workshop. Display messages
247
On-board computer and displays Z

Display messages Possible causes/consequences and
M SolutionsTire Pressure
Monitor
Inoperative No
Wheel Sensors The wheels mounted do not have a suitable tire pressure sensor.
The tire pressure monitor is deactivated.
X
Mount wheels with suitable tire pressure sensors.
The tire
pressure monitor is activated automatically after driving
for a few minutes. Check
Tire Press. The tire pressure in one or more tires has dropped significantly.
The wheel position is displayed in the multifunction display.
A warning tone also sounds.
G WARNING
With tire pressures which are too low, there is a risk of the
following hazards:
R they may burst, especially as the load and vehicle speed
increase.
R they may

wear excessively and/or unevenly, which may greatly
impair tire traction.
R the driving characteristics, as well as steering and braking, may
be greatly impaired.
There is a risk of an accident.
X Stop the vehicle without making any sudden steering or braking
maneuvers. Pay

attention to the traffic conditions as you do so.
X Secure the vehicle against rolling away ( Y page 154).
X If there is a flat tire, inspect the tires ( Y page 509).
X Check the tire pressure (Y page 534).
X If necessary, correct the tire pressure. Warning
Tire Malfunction The tire pressure in one or more tires has dropped suddenly. The
wheel position is shown in the multifunction display.
G WARNING
If you drive with a flat tire, there is a risk of the following hazards:
R A flat tire affects the ability to steer or brake the vehicle.
R You could lose control of the vehicle.
R Continued driving

with a flat tire will cause excessive heat build-
up and possibly a fire.
There is a risk of an accident.
X Stop the vehicle without making any sudden steering or braking
maneuvers. Pay

attention to the traffic conditions as you do so.
X Secure the vehicle against rolling away ( Y page 154).
X If there is a flat tire, inspect the tires ( Y page 509).248
Display messages
On-board computer and displays