2019 MERCEDES-BENZ SL CLASS check engine light

Important safety notes
GWARNING
If you operate information systems and com-
munication equipment integrated in the
vehicle when driving, you may be distracted
from the traffic situation. You could also
lose control of the vehicle. There is a risk of
an accident.
Only operate this equipment when the traffic
situation permits. If you are not sure that
this is possible, park the vehicle paying
attention to traffic conditions and operate
the equipment when the vehicle is station-
ary.
You must observe the legal requirements forthe country in which you are currently drivingwhen operating the on-board computer.
GWARNING
If the instrument cluster has failed or mal-
functioned, you may not recognize function
restrictions in systems relevant to safety.
The operating safety of your vehicle may be
impaired. There is a risk of an accident.
Drive on carefully. Have the vehicle checked
at a qualified specialist workshop immedi-
ately.
The on-board computer only shows messagesor warnings from certain systems in the multi-function display. You should therefore makesure your vehicle is operating safely at alltimes.
If the operating safety of your vehicle isimpaired, pull over as soon as it is safe to doso. Contact a qualified specialist workshop.
For an overview, see the instrument panelillustration (Ypage 33).
Displays and operation
Instrument cluster lighting
The lighting in the instrument cluster, in thedisplays and the controls in the vehicle interiorcan be adjusted using the brightness controlknob.
The brightness control knob is located on thebottom left of the instrument cluster(Ypage 33).
XTurn the brightness control knob clockwiseor counter-clockwise.If you turn the light switch (Ypage 109) totheX,`orXposition, the bright-ness will depend upon the brightness of theambient light.
The light sensor in the instrument clusterautomatically controls the brightness of themultifunction display. In daylight, the dis-plays in the instrument cluster are not illu-minated.
Speedometer with segments
The segments in the speedometer indicatewhich speed range is available.
RCruise control activated (Ypage 154):
The segments light up from the storedspeed to the maximum speed.
RActive Distance Assist DISTRONIC activated(Ypage 156):
One or two segments in the set speed rangelight up.
RActive Distance Assist DISTRONIC detects avehicle in front moving more slowly than thestored speed:
The segments between the speed of thevehicle in front and the stored speed lightup.
Tachometer
!Do not drive in the overrevving range, asthis could damage the engine.
The red band in the tachometer indicates theengine's overrevving range.
The fuel supply is interrupted to protect theengine when the red band is reached.
Outside temperature display
You should pay special attention to road con-ditions when temperatures are around freezingpoint.
190Displays and operation
On-board computer and displays

Display messagesPossible causes/consequences andPPSolutions
The yellow$warning lamp lights up and the redI(USAonly) or$(Canada only) indicator lamp flashes.
It is not possible to apply the electric parking brake manually.
XShift the transmission to position].
XVisit a qualified specialist workshop.
'(USA only)
M(Canada only)
Check Brake FluidCheck Brake FluidLevelLevel
There is not enough brake fluid in the brake fluid reservoir.
In addition, the'(USA only) orM(Canada only) warninglamp lights up in the instrument cluster and a warning tone sounds.
GWARNING
The braking effect may be impaired.
There is a risk of an accident.
XPull over and stop the vehicle safely as soon as possible, payingattention to road and traffic conditions. Do not continue drivingunder any circumstances.
XSecure the vehicle against rolling away (Ypage 146).
XConsult a qualified specialist workshop.
XDo not add brake fluid. This does not correct the malfunction.
&
Check Brake PadCheck Brake PadWearWear
The brake pads/linings have reached their wear limit.
XVisit a qualified specialist workshop.
PRE-SAFE Inopera‐PRE-SAFE Inopera‐tive See Opera‐tive See Opera‐tor's Manualtor's Manual
Important functions of PRE-SAFE®have failed. All other occupantsafety systems, e.g. air bags, remain available.
XVisit a qualified specialist workshop immediately.
Active BrakeActive BrakeAssist FunctionsAssist FunctionsCurrently LimitedCurrently LimitedSee Operator's Man‐See Operator's Man‐ualual
Active Brake Assist is temporarily inoperative.
Possible causes are:
Rthe radar sensor system is temporarily inoperative, e.g. due toelectromagnetic radiation emitted by nearby TV or radio stationsor other sources of electromagnetic radiation
Rthe system is outside the operating temperature range
Rthe on-board voltage is too low
When the causes stated above no longer apply, the display messagedisappears.
Active Brake Assist is operational again.
If the display message does not disappear:
XPull over and stop the vehicle safely as soon as possible, payingattention to road and traffic conditions.
XSecure the vehicle against rolling away (Ypage 146).
XRestart the engine.
Displaymessages211
On-b oard computer and displays
Z

XReach into the gap, pull hood catch han-dleDup and lift hoodC.
If you lift the hood by approximately 15 in(40 cm), the hood is opened and held openautomatically by the gas-filled strut.
Closing the hood
XLower the hood and let it fall from a heightof approximately 8 in (20 cm).
XCheck that the hood has engaged properly.If the hood can be raised slightly, it is notproperly engaged. Open it again and close itwith a little more force.
Engine oil
Notes on the oil level
Depending on your driving style, the vehicleconsumes up to 0.9 US qt(0.8 liters) of oil per600 miles (1,000 km). The oil consumptionmay be higher than this when the vehicle isnew or if you frequently drive at high enginespeeds.
Depending on the engine, the oil dipstick maybe in a different location.
When checking the oil level:
Rpark the vehicle on a level surface
Rthe engine should be switched off forapproximately five minutes if the engine isat normal operating temperature
Rif the engine is not at normal operating tem-perature, e.g. if the engine was only startedbriefly, wait about 30 minutes before carry-ing out the measurement
Checking the oil level using the oil dip-
stick
GWARNING
Certain components in the engine compart-
ment, such as the engine, radiator and parts
of the exhaust system, can become very
hot. Working in the engine compartment
poses a risk of injury.
Only touch the following components descri-
bed.
If work is being carried out on public roads,pay attention to the road and traffic conditionsand secure the area as appropriate.
Example
XPull out oil dipstickC.
XWipe off oil dipstickC.
XSlowly slide oil dipstickCinto the guidetube as far as it will go, and take it outagain.If the level is between MIN mark

ately with plenty of clean water and seek
medical attention.
GWARNING
A discharged battery can freeze at tempera-
tures below freezing point. When jump-start-
ing the vehicle or charging the battery,
gases can escape from the battery. There is
a risk of an explosion.
Allow the frozen battery to thaw out before
charging it or jump-starting.
!Only use battery chargers with a maximumcharging voltage of 14.8 V.
!Only charge the battery using the jump-starting connection point.
The jump-starting connection point is in theengine compartment.
If the indicator/warning lamps do not light upat low temperatures, it is very likely that thedischarged battery has frozen. In this case,you may neither charge the battery nor jump-start the vehicle. The service life of a thawed-out battery may be shorter. The starting char-acteristics can be impaired, particularly at lowtemperatures. Have the thawed-out batterychecked at a qualified specialist workshop.
Read the battery charger's operating instruc-tions before charging the battery.
XOpen the hood.
XConnect the battery charger to the positiveterminal and ground point in the same order
as when connecting the donor battery in thejump-starting procedure (Ypage 285).
Replacing the 12 V battery
Observe the notes on the 12 V battery(Ypage 282).
Mercedes-Benz recommends that you havethe 12 V battery replaced at a qualified spe-cialist workshop, e.g. at an authorizedMercedes-Benz Center.
If you want to replace the battery yourself,observe the following notes:
RAlways replace a defective battery with abattery which meets the specific require-ments of the vehicle.
The vehicle is equipped with an AGM(Absorbent Glass Mat) technology battery.Full vehicle functionality is only guaranteedwith an AGM battery. For safety reasons,Mercedes-Benz recommends that you onlyuse batteries which have been tested andapproved for your vehicle by Mercedes-Benz.
RUse detachable parts such as breatherhoses, angled connecting pieces or terminalcovers from the battery which is to bereplaced.
RMake sure that the vent hose is always con-nected to the original opening on the bat-tery side.
RInstall existing or supplied cell caps to pre-vent gases or battery acid from escaping.
RMake sure that the detachable parts areconnected again in the same way.
Jump-starting
For the jump-starting procedure, use only the jump-starting connection point in the engine com-partment, consisting of a positive terminal and a ground point.
GWARNING
Battery acid is caustic. There is a risk of injury.
Avoid contact with skin, eyes or clothing. Do not inhale any battery gases. Do not lean over the
battery. Keep children away from batteries. Wash away battery acid immediately with plenty of
clean water and seek medical attention.
Jump-starting285
Breakdown assistance
Z

GWARNING
During charging and jump-starting, explosive gases can escape from the battery. There is a
risk of an explosion.
Particularly avoid fire, open flames, creating sparks and smoking. Ensure there is sufficient
ventilation while charging and jump-starting. Do not lean over a battery.
GWARNING
During the charging process, a battery produces hydrogen gas. If a short circuit occurs or
sparks are created, the hydrogen gas can ignite. There is a risk of an explosion.
RMake sure that the positive terminal of a connected battery does not come into contact with
vehicle parts.
RNever place metal objects or tools on a battery.
RIt is important that you observe the described order of the battery terminals when connect-
ing and disconnecting a battery.
RWhen jump-starting, make sure that the battery poles with identical polarity are connected.
RIt is particularly important to observe the described order when connecting and disconnect-
ing the jumper cables.
RNever connect or disconnect the battery terminals while the engine is running.
GWARNING
A discharged battery can freeze at temperatures below freezing point. When jump-starting the
vehicle or charging the battery, gases can escape from the battery. There is a risk of an explo-
sion.
Allow the frozen battery to thaw out before charging it or jump-starting.
!Avoid repeated and lengthy starting attempts. Otherwise, the catalytic converter could bedamaged by the non-combusted fuel.
If the indicator/warning lamps do not light up at low temperatures, it is very likely that the dis-charged battery has frozen. In this case, you may neither charge the battery nor jump-start thevehicle. The service life of a thawed-out battery may be shorter. The starting characteristics canbe impaired, particularly at low temperatures. Have the thawed-out battery checked at a quali-fied specialist workshop.
Do not start the vehicle using a rapid charging device. If your vehicle's battery is discharged, theengine can be jump-started from another vehicle or from a donor battery using jumper cables.Observe the following points:
RThe battery is not accessible in all vehicles. If the other vehicle's battery is not accessible,jump-start the vehicle using a donor battery or a jump-starting device.
RYou may only jump-start the vehicle when the engine and exhaust system are cold.
RDo not start the engine if the battery is frozen. Let the battery thaw first.
ROnly jump-start from batteries with a 12 V voltage rating.
ROnly use jumper cables which have a sufficient cross-section and insulated terminal clamps.
RIf the battery is fully discharged, leave the battery that is being used to jump-start connectedfor a few minutes before attempting to start. This charges the battery slightly.
RMake sure that the two vehicles do not touch.
286Jump-starting
Breakdown assistance