2019 MERCEDES-BENZ CLA engine overheat

Holding the vehicle stationary on uphill
gradients
GWARNING
If the clutch overheats, the electronic man-
agement system is automatically deactivated.
This interrupts the power transmission. The
vehicle may, for example, roll backwards on
gradients. There is a risk of an accident.
Never hold the vehicle stationary on uphill
gradients by depressing the accelerator.
The clutch may overheat if you hold the vehiclestationary on uphill gradients by depressing theaccelerator pedal. If the clutch overheats, awarning tone sounds.
All vehicles (except Mercedes-AMG vehi-
cles):theStop Vehicle Shift to 'P'Stop Vehicle Shift to 'P'
Leave Engine RunningLeave Engine Runningdisplay messageappears in the multifunction display. You willonly be able to continue your journey once theclutch has cooled down and the display mes-sage in the multifunction display has disap-peared.
Mercedes-AMG vehicles:theTrans. OilTrans. Oil
Overheated Drive on with CareOverheated Drive on with Caredisplaymessage appears in the multifunction display.
Do not hold the vehicle stationary on uphill gra-dients by depressing the accelerator pedal.Instead, only ever hold the vehicle stationary onuphill gradients by:
Rdepressing the brake pedal
Ractivating the HOLD function
Rengaging the electric parking brake
Kickdown
Use kickdown for maximum acceleration.
XDepress the accelerator pedal beyond thepressure point.The automatic transmission shifts to a lowergear depending on the engine speed.
XEase off the accelerator pedal once thedesired speed is reached.The automatic transmission shifts back up.
Mercedes-AMG vehicles:it is only possible touse kickdown in the automatic drive programand the temporary manual drive programM.When manual drive programMis permanentlyactivated, kickdown is not possible.
For further information on kickdown in manualdrive programM(Ypage 139).
Rocking the vehicle free
Shifting back and forth between transmissionpositions[and^can help to free up thevehicle if it gets stuck in mud or snow. The vehi-cle's engine management system limits thespeed to a maximum of 5 mph (9 km/h) whenshifting back and forth. To shift repeatedlybetween transmission positions[and^,move the DIRECT SELECT lever up and downpast the point of resistance.
Drive programs
All vehicles (except Mercedes-AMG
vehicles)
Drive program C (Comfort)
Drive programCis characterized by the follow-ing:
Rthe vehicle delivers comfortable, economicalhandling characteristics.
Rthe vehicle pulls away more gently in forwardand reverse gears, unless the acceleratorpedal is depressed fully.
Rthe vehicle has improved driving stability, forexample on slippery road surfaces.
Roptimal fuel consumption resulting from theautomatic transmission shifting up sooner.The vehicle is driven in the low engine speedrange and the wheels are less likely to spin.
Drive program S (Sport)
Drive programSis characterized by the follow-ing:
Rsporty engine settings.
Rthe automatic transmission shifts up later.The fuel consumption possibly being higheras a result of the later automatic transmissionshift points.
Automatic transmission135
Driving and parking
Z

helps you to avoid overheating the brakes andwearing them out excessively.
When you take advantage of engine braking, itis possible that a drive wheel will not rotate forsome time, e.g. on a slippery road surface.This could cause damage to the drive train.This type of damage is not covered by theMercedes-Benz warranty.
Briefly depressing the accelerator pedal ondownhill gradients while the manual drive pro-gramMis temporarily activated: the automatictransmission may switch to the last active auto-matic drive programEorS. The automatic trans-mission may shift to a higher gear. This canreduce the engine's braking effect.
Heavy and light loads
GWARNING
If you rest your foot on the brake pedal while
driving, the braking system can overheat. This
increases the stopping distance and can even
cause the braking system to fail. There is a
risk of an accident.
Never use the brake pedal as a footrest. Never
depress the brake pedal and the accelerator
pedal at the same time.
!Depressing the brake pedal constantlyresults in excessive and premature wear tothe brake pads.
If the brakes have been subjected to a heavyload, do not stop the vehicle immediately. Driveon for a short while. This allows the airflow tocool the brakes more quickly.
Wet roads
If you have driven for a long time in heavy rainwithout braking, there may be a delayed reac-tion from the brakes when braking for the firsttime. This may also occur after the vehicle hasbeen washed or driven through deep water.
You have to depress the brake pedal morefirmly. Maintain a greater distance from thevehicle in front.
After driving on a wet road or having the vehiclewashed, brake firmly while paying attention tothe traffic conditions. This will warm up thebrake discs, thereby drying them more quicklyand protecting them against corrosion.
Limited braking performance on salt-
treated roads
If you drive on salted roads, a layer of salt resi-due may form on the brake discs and brakepads. This can result in a significantly longerbraking distance.
RIn order to prevent any salt build-up, apply thebrakes occasionally while paying attention tothe traffic conditions.
RCarefully depress the brake pedal and thebeginning and end of a journey.
RMaintain a greater distance to the vehicleahead.
Servicing the brakes
!The brake fluid level may be too low, if:
Rif the red brake warning lamp lights up inthe instrument cluster and
Ryou hear a warning tone while the engine isrunning
Observe additional warning messages in themultifunction display.
The brake fluid level may be too low due tobrake pad wear or leaking brake lines.
Have the brake system checked immediately.Consult a qualified specialist workshop toarrange this.
!A function or performance test should onlybe carried out on a 2-axle dynamometer. Ifyou wish to operate the vehicle on such adynamometer, please consult a qualified spe-cialist workshop in advance. You could oth-erwise damage the drive train or the brakesystem.
!As the ESP®system operates automatically,the engine and the ignition must be switchedoff (the SmartKey must be in position

For this reason, in the event of heavy rain or inconditions in which hydroplaning may occur,you must drive in the following manner:
Rlower your speed
Ravoid ruts
Ravoid sudden steering movements
Rbrake carefully
Driving on flooded roads
!Do not drive through flooded areas. Checkthe depth of any water before driving throughit. Drive slowly through standing water. Oth-erwise, water could enter the vehicle interioror engine compartment. It can then damagethe engine's or automatic transmission'selectronic components. It can also be suckedin by the engine's air intake connection andcause engine damage.
Winter driving
GWARNING
If you shift down on a slippery road surface in
an attempt to increase the engine's braking
effect, the drive wheels could lose their grip.
There is an increased danger of skidding and
accidents.
Do not shift down for additional engine brak-
ing on a slippery road surface.
GDANGER
If the exhaust pipe is blocked or adequate
ventilation is not possible, poisonous gases
such as carbon monoxide (CO) may enter the
vehicle. This is the case, e.g. if the vehicle
becomes trapped in snow. There is a risk of
fatal injury.
If you leave the engine or the auxiliary heating
running, make sure the exhaust pipe and area
around the vehicle are clear of snow. To
ensure an adequate supply of fresh air, open a
window on the side of the vehicle that is not
facing into the wind.
Have your vehicle winter-proofed at a qualifiedspecialist workshop at the onset of winter.
Drive particularly carefully on slippery road sur-faces. Avoid sudden acceleration, steering andbraking maneuvers. Do not use cruise control orActive Distance Assist DISTRONIC.
If the vehicle threatens to skid or cannot bestopped when moving at low speed:
XShift the transmission to position\\.
XTry to bring the vehicle under control usingcorrective steering.
The outside temperature indicator is notdesigned to serve as an ice-warning device andis therefore unsuitable for that purpose.Changes in the outside temperature are dis-played after a short delay.
Indicated temperatures just above the freezingpoint do not guarantee that the road surface isfree of ice. The road may still be icy, especially inwooded areas or on bridges.
You should pay special attention to road condi-tions when temperatures are around freezingpoint.
For more information on driving with snowchains, see (Ypage 293).
For more information on driving with summertires, see (Ypage 292).
Observe the notes in the "Winter operation" sec-tion (Ypage 292).
Driving systems
Cruise control
General notes
Cruise control maintains a constant road speedfor you. It brakes automatically in order to avoidexceeding the set speed. On long and steepdownhill gradients, especially if the vehicle isladen, you must select a low gear in good time.You need to shift manually using the steeringwheel paddle shifters beforehand. By doing so,you will make use of the braking effect of theengine. This relieves the load on the brake sys-tem and prevents the brakes from overheatingand wearing too quickly.
When the engine is running, you can use thecruise control lever to limit the speed to anyspeed between 20 mph (30 km/h) and the tech-nically permitted maximum speed of the vehicle.
Use cruise control if road and traffic conditionsmake it appropriate to maintain a steady speedfor a prolonged period.
150Driving systems
Driving and parking

There is a short delay before a change in outsidetemperature appears in the multifunction dis-play.
Coolant temperature gauge
GWARNING
Opening the hood when the engine is over-
heated or when there is a fire in the engine
compartment could expose you to hot gases
or other service products. There is a risk of
injury.
Let an overheated engine cool down before
opening the hood. If there is a fire in the
engine compartment, keep the hood closed
and contact the fire department.
!A display message is shown if the coolanttemperature is too high.
If the coolant temperature is over 248 ‡(120 †), do not continue driving. The enginewill otherwise be damaged.
The coolant temperature gage is in the instru-ment cluster on the right-hand side (Ypage 33).
TheHmarking in the coolant temperature gaugecorresponds to a coolant temperature ofapproximately 248 ‡ (120 †).
Under normal operating conditions and at thecorrect coolant level, the coolant temperaturegauge may rise to theHmarking.
Operating the on-board computer
Overview
CMultifunction display
DRight control panel

Display messagesPossible causes/consequences andPPSolutions
=
See Operator's Man‐See Operator's Man‐ualual
The battery is not being charged.
A warning tone also sounds.
Possible causes are:
Ra defective alternator
Ra torn poly-V-belt
Ra malfunction in the electronics
!Do not drive any further. Otherwise the engine may overheat.
XPull over and stop the vehicle safely and switch off the engine, pay-ing attention to road and traffic conditions.
XSecure the vehicle against rolling away (Ypage 142).
XConsult a qualified specialist workshop.
=
Stop Vehicle SeeStop Vehicle SeeOperator's ManualOperator's Manual
The battery is no longer being charged and the condition of charge istoo low.
A warning tone also sounds.
XPull over and stop the vehicle safely and switch off the engine, pay-ing attention to road and traffic conditions.
XSecure the vehicle against rolling away (Ypage 142).
XObserve the instructions in the display message=See Oper‐See Oper‐ator's Manualator's Manual.
XConsult a qualified specialist workshop.

Display messagesPossible causes/consequences andPPSolutions
Stop Vehicle ShiftStop Vehicle Shiftto P Leave Engineto P Leave EngineRunningRunning
The automatic transmission has overheated.
XDrive on carefully.The automatic transmission is available again when the displaymessage goes out.
If the multifunction display still shows the display message:
XPull over and stop the vehicle safely as soon as possible, payingattention to road and traffic conditions.
XSecure the vehicle against rolling away (Ypage 142).
XWait until the automatic transmission has cooled down and the dis-play message has disappeared.
Auxiliary BatteryAuxiliary BatteryMalfunctionMalfunctionThe auxiliary battery for the automatic transmission is no longer beingcharged.
XVisit a qualified specialist workshop.
XUntil then, always shift the transmission to position]before youswitch off the engine.
XBefore leaving the vehicle, apply the electric parking brake.
Trans. Oil Overhea‐Trans. Oil Overhea‐ted Drive on withted Drive on withCareCare
Mercedes-AMG vehicles: the transmission oil has overheated.
Manual drive programcand the temporarily active manual driveprogram are no longer available. The engine power output is reduced.
XAllow the vehicle to cool down.
4matic Currently4matic CurrentlyUnavailableUnavailable4MATIC has overheated. The vehicle is only driven by the front wheels.
XDrive on.The airflow cools 4MATIC more quickly.
When the display message goes out, 4MATIC is available again andthe vehicle is driven by all four wheels.
4matic Inoperative4matic Inoperative4MATIC is malfunctioning. The vehicle is only driven by the frontwheels.
XVisit a qualified specialist workshop.

Engine compartment
Hood
Important safety notes
GWARNING
If the hood is unlatched, it may open up when
the vehicle is in motion and block your view.
There is a risk of an accident.
Never unlatch the hood while driving. Before
every trip, ensure that the hood is locked.
GWARNING
When opening and closing the hood, it may
suddenly fall into the closed position. There is
a risk of injury to persons within range of
movement of the hood.
Open and close the hood only when no one is
within its range of movement.
GWARNING
Opening the hood when the engine is over-
heated or when there is a fire in the engine
compartment could expose you to hot gases
or other service products. There is a risk of
injury.
Let an overheated engine cool down before
opening the hood. If there is a fire in the
engine compartment, keep the hood closed
and contact the fire department.
GWARNING
The engine compartment contains moving
components. Certain components, such as
the radiator fan, may continue to run or start
again suddenly when the ignition is off. There
is a risk of injury.
If you need to do any work inside the engine
compartment:
Rswitch off the ignition
Rnever reach into the area where there is a
risk of danger from moving components,
such as the fan rotation area
Rremove jewelry and watches
Rkeep items of clothing and hair, for exam-
ple, away from moving parts
GWARNING
The ignition system and the fuel injection sys-
tem work under high voltage. If you touch
components which are under voltage, you
could get an electric shock. There is a risk of
injury.
Never touch components of the ignition sys-
tem or fuel injection system when the ignition
is switched on.
To ensure the flow of fresh air through the airvents into the vehicle interior, please observethe following notes (Ypage 121):
Opening the hood
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.
Where possible, let the engine cool down and
touch only the components described in the
following.
GWARNING
When the hood is open and the windshield
wipers are set in motion, you can be injured by
the wiper linkage. There is a risk of injury.
Always switch off the windshield wipers and
the ignition before opening the hood.
!Make sure that the windshield wipers arenot folded away from the windshield. Youcould otherwise damage the windshield wip-ers or the hood.
260Engine compartment
Maintenance and care

Coolant
Important safety notes
GWARNING
If antifreeze comes into contact with hot com-
ponents in the engine compartment, it may
ignite. There is a risk of fire and injury.
Let the engine cool down before you add anti-
freeze. Make sure that antifreeze is not spilled
next to the filler neck. Thoroughly clean the
antifreeze from components before starting
the engine.
!Only add coolant that has been premixedwith the desired antifreeze protection. Youcould otherwise damage the engine.
You can find additional notes on the coolant inthe following places:
Rin the Mercedes-Benz Specifications forService Products, MB BeVo 310.1
-on the Internet athttp://bevo.mercedes-benz.com
-on the Mercedes-Benz BeVo app
Ra qualified specialized workshop
!Always use a suitable coolant mixture, evenin countries where high temperatures prevail.
Otherwise, the engine cooling system is notsufficiently protected from corrosion andoverheating.
iHave the coolant regularly replaced at aqualified specialist workshop and the replace-ment confirmed in the Maintenance Booklet.
Comply with the important safety notes for ser-vice products when handling coolant(Ypage 319).
The coolant is a mixture of water and corrosioninhibitor/antifreeze concentrate. It performsthe following tasks:
Ranti-corrosion protection
Rantifreeze protection
Rraising the boiling point
If the coolant has antifreeze protection down to-35 ‡ (-37 †), the boiling point of the coolantduring operation is approximately 266 ‡(130 †).
The antifreeze concentrate/corrosion inhibitorconcentration in the engine cooling systemshould:
Rbe at least 50%. This will protect the enginecooling system against freezing down toapproximately -35 ‡ (-37 †)
Rnot exceed 55% (antifreeze protection downto -49‡[-45 †]). Otherwise, heat will not bedissipated as effectively
Mercedes-Benz recommends a coolant or cor-rosion inhibitor/antifreeze concentrate inaccordance withMB Specifications for Service Products 310.1.
iWhen the vehicle is first delivered, it is filledwith a coolant mixture that ensures adequateantifreeze and anti-corrosion protection.
iThe coolant is checked with every mainte-nance interval at a qualified specialist work-shop.
Filling capacities
ModelCapacity
Mercedes‑AMGvehiclesApprox. 12.6 US qt(11.9l)
All other modelsApprox. 8.2 US qt(7.8 l)
Windshield washer system
Important safety notes
GWARNING
Windshield washer concentrate could ignite if
it comes into contact with hot engine compo-
nents or the exhaust system. There is a risk of
fire and injury.
Make sure that no windshield washer con-
centrate is spilled next to the filler neck.
!Only MB SummerFit and MB WinterFitwasher fluid should be mixed together. Thespray nozzles may otherwise becomeblocked.
Do not use distilled or de-ionized water. Other-wise, the level sensor may give a false reading.
Service products and filling capacities323
Technical data
Z