ECU MERCEDES-BENZ SL CLASS 2019 Workshop Manual

iJumper cables and further information regarding jump-starting can be obtained at any quali-fied specialist workshop.
Towing and tow-starting
Important safety notes
GWARNING
When towing or tow-starting another vehicle
and its weight is greater than the permissi-
ble gross weight of your vehicle, the:
Rthe towing eye could detach itself
Rthe vehicle/trailer combination could roll-
over.
There is a risk of an accident.
When towing or tow-starting another vehi-
cle, its weight should not be greater than
the permissible gross weight of your vehicle.
Details on the permissible gross vehicle weightof your vehicle can be found on the vehicleidentification plate (Ypage 320).
!When Active Brake Assist, Active DistanceAssist DISTRONIC or the HOLD function isactivated, the vehicle brakes automaticallyin certain situations.
To avoid damage to the vehicle, deactivatethese systems in the following or similar sit-uations:
Rwhen towing the vehicle
Rin the car wash
!Only secure the tow rope or tow bar at thetowing eyes. Otherwise, the vehicle could bedamaged.
!Do not use the towing eye for recovery,this could damage the vehicle. If in doubt,recover the vehicle with a crane.
!When towing, pull away slowly andsmoothly. If the tractive power is too high,the vehicles could be damaged.
!Do not tow with sling-type equipment. Thiscould damage the vehicle.
!When towing away vehicles with KEYLESS-GO, use the key instead of the Start/Stopbutton. The automatic transmission mayotherwise shift to position]when you
open the driver's or front-passenger door,which could damage the transmission.
!Make sure that the electric parking brakeis released. If the electric parking brake isfaulty, visit a qualified specialist workshop.
!You may tow the vehicle for a maximumdistance of 30 miles (50 kilometers). A tow-ing speed of 30 mph (50 km/h) must not beexceeded.
For towing distances over 30 miles(50 kilometers), the entire vehicle must beraised and transported.
!When you are tow-starting or towinganother vehicle, its weight must not exceedthe maximum permissible gross weight ofyour vehicle.
It is better to have the vehicle transportedthan to have it towed away.
The automatic transmission must be in posi-tion\\when the vehicle is being towed away.
The battery must be connected and charged.Otherwise, you:
Rcannot turn the SmartKey to positionHinthe ignition lock
Rcannot shift the automatic transmission toposition\\
Deactivate the automatic locking featurebefore the vehicle is towed (Ypage 201). Youcould otherwise be locked out when pushingor towing the vehicle.
Installing/removing the towing eye
Installing the towing eye
GWARNING
The exhaust tail pipe may be very hot. There
is a risk of burns when removing the rear
cover.
Do not touch the exhaust pipe. Take particu-
lar care when removing the rear cover.
288Towing and tow-starting
Breakdown assistance

When towing away, use a towing rope or atowing bar with both axles on the ground. Donot use any tow bar systems.
Towing the vehicle with the rear axle
raised
!The ignition must be switched off if youare towing the vehicle with the rear axle
raised. Intervention by ESP®could other-wise damage the brake system.
!Vehicles with automatic transmission mustnot be towed with the rear axle raised. Thevehicle/trailer combination may otherwiseswerve or even roll over.
Transporting the vehicle
Vehicles with automatic transmission
!When the vehicle is loaded for transport,the front and rear axles must be stationaryand on the same transportation vehicle.Positioning over the connection point of thetransport vehicle is not permitted. The drivetrain may otherwise be damaged.
All vehicles
!You may only secure the vehicle by thewheels, not by parts of the vehicle such asaxle or steering components. Otherwise, thevehicle could be damaged.
The towing eye can be used to pull the vehicleonto a trailer or transporter for transportingpurposes.
XTurn the SmartKey to positionHin the igni-tion lock.
XShift the transmission to position\\.
As soon as the vehicle has been loaded:
XPrevent the vehicle from rolling away byapplying the electric parking brake.
XShift the transmission to position].
XTurn the SmartKey to position

Overinflated tires may:
Rincrease the braking distance
Radversely affect handling
Rwear excessively and/or unevenly
Rhave an adverse effect on ride comfort
Rbe more susceptible to damage
Maximum tire pressures
CExample: maximum permissible tire pres-sure
Never exceed the maximum permissible tireinflation pressure. Always observe the recom-mended tire pressure for your vehicle whenadjusting the tire pressure (Ypage 296).
iThe actual values for tires are vehicle-spe-cific and may deviate from the values in theillustration.
Checking the tire pressures
Important safety notes
The tire pressure monitor does not warn youof:
Rincorrectly set tire pressure
Rsudden loss of tire pressure, e.g. from a for-eign object that has penetrated the tire
Observe the notes on tire pressure(Ypage 296).
Information on air pressure for the tires onyour vehicle can be found:
Ron the vehicle's Tire and Loading Informa-tion placard on the B-pillar
Ron the tire pressure table in the fuel fillerflap
Rin the "Tire pressure" section
Checking tire pressures manually
To determine and set the correct tire pressure,proceed as follows:
XRemove the valve cap of the tire that is tobe checked.
XPress the tire pressure gauge securely ontothe valve.
XRead the tire pressure and compare it to therecommended value on the Tire and LoadingInformation placard or the tire pressuretable (Ypage 296).
XIf the tire pressure is too low, increase thetire pressure to the recommended value.
XIf the tire pressure is too high, release air.To do so, press down the metal pin in thevalve, using the tip of a pen for example.Then check the tire pressure again using thetire pressure checker.
XScrew the valve cap onto the valve.
XRepeat these steps for the other tires.
Tire pressure monitor
General notes
If a tire pressure monitor is installed, the vehi-cle's wheels have sensors that monitor the tirepressures in all four tires. The tire pressuremonitor warns you if the pressure drops in oneor more of the tires. The tire pressure monitoronly functions if the corresponding sensorsare installed in all wheels.
Information on tire pressures is displayed inthe multifunction display. After a few minutesof driving, the current tire pressure of each tireis shown in theServ.Serv.menu of the multifunc-tion display.
Example: current tire pressure display
For information on the message display, referto the "Checking the tire pressure electroni-cally" section (Ypage 301).
Tire pressure299
Wheels and tires
Z

stantly, the tire pressure monitor is malfunc-tioning.
In addition to the warning lamp, a messageappears in the multifunction display. Observethe information on display messages(Ypage 227).
It may take up to ten minutes for a malfunc-tion of the tire pressure monitor to be indica-ted. A malfunction will be indicated by the tirepressure warning lamp flashing for approx-imately one minute and then remaining lit.When the malfunction has been rectified, thetire pressure warning lamp goes out after afew minutes of driving.
The tire pressure values indicated by the on-board computer may differ from those meas-ured at a gas station with a pressure gage. Thetire pressures shown by the on-board com-puter refer to those measured at sea level. Athigh altitudes, the tire pressure values indica-ted by a pressure gage are higher than thoseshown by the on-board computer. In this case,do not reduce the tire pressures.
The operation of the tire pressure monitor canbe affected by interference from radio trans-mitting equipment (e.g. radio headphones,two-way radios) that may be being operated inor near the vehicle.
Checking the tire pressure electroni-
cally
XMake sure that the SmartKey is in positionH(Ypage 126) in the ignition lock.
XPress theYorebutton on the steer-ing wheel to select theServ.Serv.menu.
XPress thecordbutton to selectTire PressureTire Pressure.
XPressv.The current tire pressure of each tire isshown in the multifunction display.
If the vehicle has been parked for over20 minutes, theTire pressure will beTire pressure will bedisplayed after driving a few minutesdisplayed after driving a few minutesmessage appears.
After a teach-in process, the tire pressuremonitor automatically detects new wheels ornew sensors. As long as a clear allocation ofthe tire pressure value to the individual wheelsis not possible, theTire Pressure MonitorTire Pressure MonitorActiveActivedisplay message is shown instead ofthe tire pressure display. The tire pressuresare already being monitored.
Tire pressure monitor warning mes-
sages
The tire pressure monitor detects a pressureloss in one or more tires:
RIf the tire pressure monitor detects a pres-sure loss in one or more tires, a warningmessage is shown in the multifunction dis-play. The yellow tire pressure warning lampthen lights up.
RIf thePlease Correct Tire PressurePlease Correct Tire Pressuremessage appears in the multifunction dis-play, the tire pressure in at least one tire istoo low. The tire pressure must be correctedwhen the opportunity arises.
RIf theCheck TiresCheck Tiresmessage appears in themultifunction display, the tire pressure in atleast one tire has dropped significantly. Thetires must be checked.
RIf theWarning Tire MalfunctionWarning Tire Malfunctionmes-sage appears in the multifunction display,the tire pressure in at least one tire hasdropped suddenly. The tires must bechecked.
Observe the instructions and safety notes inthe display messages in the "Tires" section(Ypage 227).
If the wheel positions on the vehicle are rota-ted, the tire pressures may be displayed forthe wrong positions for a short time. This isrectified after a few minutes of driving, and thetire pressures are displayed for the correctpositions.
Restarting the tire pressure monitor
When you restart the tire pressure monitor, allexisting warning messages are deleted and thewarning lamps go out. The monitor uses thecurrently set tire pressures as the referencevalues for monitoring. In most cases, the tirepressure monitor will automatically detect thenew reference values after you have changedthe tire pressure. However, you can also setreference values manually as described here.The tire pressure monitor then monitors thenew tire pressure values.
XSet the tire pressure to the value recom-mended for the corresponding driving situa-tion on the Tire and Loading Informationplacard on the driver's side B-pillar(Ypage 296).
Tire pressure301
Wheels and tires
Z

Maximum loaded vehicle weight
The maximum weight is the sum of:
Rthe curb weight of the vehicle
Rthe weight of the accessories
Rthe load limit
Rthe weight of the factory installed optionalequipment
Kilopascal (kPa)
Metric unit for tire pressure. 6.9 kPa corre-sponds to 1 psi. Another unit for tire pressureis bar. 100 kilopascals (kPa) are the equivalentof 1 bar.
Load index
In addition to the load-bearing index, the loadindex may also be imprinted on the sidewall ofthe tire. This specifies the load-bearing capa-city more precisely.
Curb weight
The weight of a vehicle with standard equip-ment including the maximum capacity of fuel,oil and coolant. It also includes the air-condi-tioning system and optional equipment if theseare installed in the vehicle, but does notinclude passengers or luggage.
Maximum load rating
The maximum load rating is the maximum per-missible weight in kilograms or lbs for which atire is approved.
Maximum permissible tire pressure
Maximum permissible tire pressure for onetire.
Maximum load on one tire
Maximum load on one tire. This is calculatedby dividing the maximum axle load of one axleby two.
PSI (pounds per square inch)
A standard unit of measure for tire pressure.
Aspect ratio
Relationship between tire height and tire widthin percent.
Tire pressure
This is pressure inside the tire applying an out-ward force to each square inch of the tire'ssurface. The tire pressure is specified in
pounds per square inch (psi), in kilopascal(kPa) or in bar. The tire pressure should onlybe corrected when the tires are cold.
Cold tire pressure
The tires are cold:
Rif the vehicle has been parked with the tiresout of direct sunlight for at least three hoursand
Rif the vehicle has not been driven furtherthan 1 mile (1.6 km)
Tread
The part of the tire that comes into contactwith the road.
Bead
The tire bead ensures that the tire sitssecurely on the wheel. There are several steelwires in the bead to prevent the tire from com-ing loose from the wheel rim.
Sidewall
The part of the tire between the tread and thebead.
Weight of optional extras
The combined weight of those optional extrasthat weigh more than the replaced standardparts and more than 2.3 kg (5 lbs). Theseoptional extras, such as high-performancebrakes, level control, a roof rack or a high-per-formance battery, are not included in the curbweight and the weight of the accessories.
TIN (Tire Identification Number)
This is a unique identifier which can be usedby a tire manufacturer to identify tires, forexample for a product recall, and thus identifythe purchasers. The TIN is made up of themanufacturer's identity code, tire size, tiretype code and the manufacturing date.
Load bearing index
The load bearing index (also load index) is acode that contains the maximum load bearingcapacity of a tire.
Traction
Traction is the result of friction between thetires and the road surface.
312All about wheels and tires
Wheels and tires

XShift the transmission to position].
XSwitch off the engine.
XVehicles without KEYLESS-GO:removethe SmartKey from the ignition lock.
XVehicles with KEYLESS-GO:open the driv-er's door.The vehicle electronics now have status0.This is the same as the SmartKey havingbeen removed.
XVehicles with KEYLESS-GO:remove theStart/Stop button from the ignition lock(Ypage 126).
XIf included in the vehicle equipment, removethe tire-change tool kit from the vehicle.
XSafeguard the vehicle against rolling away.
Securing the vehicle to prevent it from
rolling away
If your vehicle is equipped with a wheel chock,it can be found in the tire-change tool kit(Ypage 277).
The folding wheel chock is an additional safetymeasure to prevent the vehicle from rollingaway, for example when changing a wheel.
XFold both plates upwardsC.
XFold out lower plateD.
XGuide the lugs on the lower plate fully intothe openings in base plate

GWARNING
If you tighten the wheel bolts or wheel nuts
when the vehicle is raised, the jack could tip
over. There is a risk of injury.
Only tighten the wheel bolts or wheel nuts
when the vehicle is on the ground.
Always pay attention to the instructions andsafety notes in the "Changing a wheel" section(Ypage 313).
Only use wheel bolts that have been designedfor the wheel and the vehicle. For safety rea-sons, Mercedes-Benz recommends that youonly use wheel bolts which have beenapproved for Mercedes-Benz vehicles and therespective wheel.
!Mercedes-AMG vehicles:during removaland repositioning of the wheel, the wheelrim can strike the ceramic-brake disc anddamage it. Therefore, you should proceedcarefully and get a second person assist toyou. Alternatively, you can use a secondalignment bolt.
!To prevent damage to the paintwork, holdthe wheel securely against the wheel hubwhile screwing in the first wheel bolt.
XClean the wheel and wheel hub contact sur-faces.
XSlide the wheel to be mounted onto thealignment bolt and push it on.
XTighten the wheel bolts until they are finger-tight.
XUnscrew the alignment bolt.
XTighten the last wheel bolt until it is finger-tight.
Lowering the vehicle
GWARNING
The wheels could come loose if the wheel
bolts or wheel nuts are not tightened to the
prescribed tightening torque. There is a risk
of an accident.
Ensure that the wheel bolts or wheel nuts
are tightened to the prescribed tightening
torque.
If you are not sure, do not move the vehicle.
Contact a qualified specialist workshop and
have the tightening torque checked immedi-
ately.
XTurn the crank of the jack counter-clockwiseuntil the vehicle is once again standingfirmly on the ground.
XPlace the jack to one side.
XTighten the wheel bolts evenly in a cross-wise pattern in the sequence indicated (Cto