2017 MERCEDES-BENZ E-Class CABRIOLET check engine light

Problems with the windshield wipers
ProblemPossible causes/consequences andMSolutions
The windshield wipers
are jammed.Leaves or snow, for example, may be obstructing the windshield wiper
movement. The wiper motor has been deactivated.
XFor safety reasons, you should remove the SmartKey from the igni-
tion lock.
or
XSwitch off the engine using the Start/Stop button and open the
driver's door.
XRemove the cause of the obstruction.
XSwitch the windshield wipers back on.
The windshield wipers
fail completely.The windshield wiper drive is malfunctioning.
XSelect another wiper speed on the combination switch.
XHave the windshield wipers checked at a qualified specialist work-
shop.
116Windshield wipers
Lights and windshield wipers

Problems with the engine
ProblemPossible causes/consequences andMSolutions
The engine does not
start. The starter motor
can be heard.RThere is a malfunction in the engine electronics.
RThere is a malfunction in the fuel supply.
Before attempting to start the engine again:
XTurn the Smartkey back to position 0in the ignition lock.
or
XPress the Start/Stop button repeatedly until all indicator lamps in
the instrument cluster go out.
XTry to start the engine again (Ypage 129). Avoid excessively long
and frequent attempts to start the engine as these will drain the
battery.
If the engine does not start after several attempts:
XConsult a qualified specialist workshop.
The engine does not
start. You cannot hear
the starter motor.The on-board voltage is too low because the battery is too weak or
discharged.
XJump-start the vehicle (Ypage 278).
If the engine does not start despite attempts to jump-start it:
XConsult a qualified specialist workshop.
The starter motor was exposed to a thermal load that was too high.
XAllow the starter motor to cool down for approximately two minutes.
XTry to start the engine again.
If the engine still does not start:
XConsult a qualified specialist workshop.
The engine is not running
smoothly and is misfir-
ing.There is a malfunction in the engine electronics or in a mechanical
component of the engine management system.
XOnly depress the accelerator pedal slightly.
Otherwise, non-combusted fuel may get into the catalytic converter
and damage it.
XHave the cause rectified immediately at a qualified specialist work-
shop.
The coolant temperature
gauge shows a value
above 248 ‡ (120 †).The coolant level is too low. The coolant is too hot and the engine is no
longer being cooled sufficiently.
XStop as soon as possible and allow the engine and the coolant to
cool down.
XCheck the coolant level (Ypage 259). Observe the warning notes
as you do so and add coolant if necessary.
Driving133
Driving and parking
Z

You have to depress the brake pedal more
firmly. Maintain a greater distance from the
vehicle in front.
After driving on a wet road or having the vehicle
washed, brake firmly while paying attention to
the traffic conditions. This will warm up the
brake discs, thereby drying them more quickly
and 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 brake
pads. This can result in a significantly longer
braking distance.
RIn order to prevent any salt build-up, apply the
brakes occasionally while paying attention to
the traffic conditions.
RCarefully depress the brake pedal and the
beginning and end of a journey.
RMaintain a greater distance to the vehicle
ahead.
Servicing the brakes
!The brake fluid level may be too low, if:
Rif the red brake warning lamp lights up in
the instrument cluster and
Ryou hear a warning tone while the engine is
running
Observe additional warning messages in the
multifunction display.
The brake fluid level may be too low due to
brake pad wear or leaking brake lines.
Have the brake system checked immediately.
Consult a qualified specialist workshop to
arrange this.
!Vehicles with 4MATIC: function or per-
formance tests may only be carried out on a 2-
axle dynamometer. If you wish to operate the
vehicle on such a dynamometer, please con-
sult a qualified specialist workshop in
advance. You could otherwise damage the
drive train or the brake system.
!Vehicles with 4MATIC: as the ESP®sys-
tem operates automatically, the engine and
the ignition must be switched off (SmartKey in
position 0or 1in the ignition lock or Start/
Stop button in position 0or 1) while the park- ing brake is being tested on a brake dyna-
mometer.
Braking maneuvers triggered automatically
by ESP
®may seriously damage the brake sys-
tem.
!Vehicles with 4MATIC: as the ESP®sys-
tem operates automatically, the engine and
the ignition system must be switched off
(SmartKey in position 0or 1in the ignition
lock or Start/Stop button in position 0or 1)
when:
Rtesting the parking brake on a brake dyna-
mometer.
Ryou intend to have the vehicle towed with
the front axle raised.
Braking maneuvers triggered automatically
by ESP
®may seriously damage the brake sys-
tem.
All checks and maintenance work on the brake
system must be carried out at a qualified spe-
c

ialist workshop.
Have brake pads installed and brake fluid
replaced at a qualified specialist workshop.
If the brake system has only been subject to
moderate loads, you should test the functional-
ity of your brakes at regular intervals. To do so,
press firmly on the brake pedal when driving at a
high speed. This improves the grip of the brake
pads.
You can find a description of Brake Assist (BAS) on (
Ypage 62) or of BAS PLUS with Cross-Traffic
Assist on (Ypage 62).
The braking characteristics of the vehicle can be
seriously impaired if:
Rbrake pads other than those recommended
are installed
Rthe recommended brake fluid is not used
Safe braking can no longer be guaranteed.
Driving on wet roads
Hydroplaning
If water has accumulated to a certain depth on
the road surface, there is a danger of hydro-
planing occurring, even if:
Ryou drive at low speeds.
Rthe tires have adequate tread depth.
Driving tips149
Driving and parking
Z

Display messagesPossible causes/consequences andMSolutions
$(USA
only)
J( Canada
only)
Check Brake Fluid
Level
There is no tenough brak eflui din th ebrak efluid reservoir .
In addition ,th e$ (USAonly) or J(Canada only) warning lamp
lights up in th einstrumen tcluste rand awarning tone sounds.
GWARNIN G
The braking effec tmay be impaired.
There is aris kof an accident.
XPull ove rand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions. Do no tcontinu edrivin g
under any circumstances.
XSecur eth evehicl eagainst rollin gaway (Ypage 144).
XConsult aqualified specialist workshop .
XDo notadd brak efluid .This does no tcorrec tth emalfunction .
#
CheckBrakePadWear
The brak epads/linings hav ereached their wear limit.
XVisit aqualified specialist workshop .
G
mbrace Inoperative
Oneor mor emain features of th embrace system are malfunctioning .
XVisitaqualified specialist workshop .
Collision Preven‐tionAssist Plu sCurrently Unavaila‐ble See Operator' sManual
COLLISION PREVENTION ASSIST PLU Sis temporarily no toperational.
Possibl ecauses are:
Rth eradar sensor system is temporarily inoperative, e.g. due to elec -
tromagneti cradiation emitted by nearby TV or radi ostation sor
other source sof electromagneti cradiation .
Rthesystem is outside th eoperating temperature range.
Rth eon-boar dvoltag eis to olow.
Whe nth ecauses state dabov eno longer apply, th edisplay message
disappears.
COLLISION PREVENTION ASSIST PLU Sis operational again .
If th edisplay message does no tdisappear :
XPull overand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions.
XSecur eth evehicl eagainst rollin gaway (Ypage 144).
XRestart th eengine.
Collision Preven ‐tionAssist Plu sInoperative
COLLISION PREVENTION ASSIST PLU Sis temporarily inoperative due
to amalfunction .Adaptive Brake Assis tmay also hav efailed.
XVisit aqualified specialist workshop .
PRE-SAFE
Inoperative SeeOperator'sManual
Importan tfunction sof PRE-SAF E®havefailed. Al lother occupant
safet ysystems ,e.g. air bags ,remain available.
XVisit aqualified specialist workshop .
Display messages205
On-board computer and displays
Z

Engine
Warning/
indicator
lampNSignal type
Possible causes/consequences and M
Solutions
;NThe yellow Check Engine warning lamp lights up while the engine is running.
There may be a malfunction, for example:
Rin the engine management
Rin the fuel injection system
Rin the exhaust system
Rin the ignition system
Rin the fuel system
The emission limit values may be exceeded and the engine may be in emergency
mode.
XVisit a qualified specialist workshop immediately.
iIn some states, you must immediately visit a qualified specialist workshop as
soon as the yellow Check Engine warning lamp lights up. This is due to the legal
requirements in effect in these states. If in doubt, check whether such legal
regulations apply in the state in which you are currently driving.
8N The yellow reserve fuel warning lamp lights up while the engine is running.
The fuel level has dropped into the reserve range.
XRefuel at the nearest gas station.
8N The yellow reserve fuel warning lamp flashes while the vehicle is in motion.
In addition, the ;Check Engine warning lamp may light up.
The fuel filler cap is not closed correctly or the fuel system is leaking.
XCheck that the fuel filler cap is correctly closed.
XIf the fuel filler cap is not correctly closed: close the fuel filler cap.
XIf the fuel filler cap is closed:visit a qualified specialist workshop.
?NThe red coolant warning lamp lights up while the engine is running and the
coolant temperature gage is at the start of the scale.
The temperature sensor for the coolant temperature gage is defective.
The coolant temperature is no longer being monitored. There is a risk of engine
damage if the coolant temperature is too high.
XPull over and stop the vehicle safely and switch off the engine, paying attention
to road and traffic conditions. Do not continue driving under any circumstances.
XSecure the vehicle against rolling away (Ypage 144).
XConsult a qualified specialist workshop.
230Warning and indicator lamps in the instrument cluster
On-board computer and displays

XMake sure that the windshield wipers are
turned off.
XPull release lever:on the hood.
The hood is released.
XReach into the gap, pull hood catch handle ;
up and lift the hood.
If you lift the hood by approximately 15 in
(40 cm), the hood is opened and held open
automatically by the gas-filled strut.
Closing the hood
XLower the hood and let it fall from a height of
approximately 8 in (20 cm).
XCheck that the hood has engaged properly.
If the hood can be raised slightly, it is not
properly engaged. Open it again and close it
with a little more force.
Engine oil
General notes
Depending on your driving style, the vehicle
consumes up to 0.9 US qt (0.8 liters) of oil per
600 miles (1,000 km). The oil consumption may be higher than this when the vehicle is new or if
you frequently drive at high engine speeds.
Depending on the engine, the oil dipstick may be
in a different location.
When checking the oil level:
Rpark the vehicle on a level surface.
Rthe engine should be switched off for approx-
imately five minutes if the engine is at normal
operating temperature.
Rif the engine is not at normal operating tem-
perature, e.g. if the engine was only started
briefly, wait about 30 minutes before carrying
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.
Where possible, let the engine cool down and touch only the components described in the
following.
XPull oil dipstick :out of the dipstick guide
tube.
XWipe off oil dipstick :.
XSlowly slide oil dipstick :into the guide tube
to the stop, and take it out again.
If the level is between MIN mark =and MAX
mark ;, the oil level is correct.
XIf the oil level has dropped to MIN mark =or
below, add 1.1 US qt (1.0 liter) of engine oil.
258Engine compartment
Maintenance and care

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.
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 ven-
tilation 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 connecting
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 disconnecting
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 explosion. Allow the frozen battery to thaw out before charging it or jump-starting.
!Avoid repeated and lengthy starting attempts. Otherwise, the catalytic converter could be
damaged by the non-combusted fuel.
If, at low temperatures, the indicator lamps/warning lamps in the instrument cluster do not light up,
it is highly likely that the discharged 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 characteristics can be impaired, particularly at low temperatures. Have the thawed-out
battery checked at a qualified specialist workshop.
278Jump-starting
Breakdown assistance