2021 CITROEN C3 AIRCROSS check engine

133
Practical information
7Engine coolant
It is normal to top up this fluid between two services.
The check and top-up must only be done with
the engine cold.
A low level presents a risk of serious damage to
the engine.
The level of this fluid should be close to the
"MAX" mark but should never exceed it.
If the level is close to or below the " MIN” mark, it
is essential to top up.
When the engine is hot, the temperature of this
fluid is regulated by the fan.
As the cooling system is pressurised, wait at
least one hour after switching off the engine
before carrying out any work.
In order to avoid the risk of scalding if you need
to top up in an emergency, wrap a cloth around
the cap and unscrew the cap by two turns to
allow the pressure to drop.
Once the pressure has dropped, remove the cap
and top up to the required level.
Cooling of the engine when stopped
The engine cooling fan may start after
the engine has been switched off.
Take care with objects or clothing that
could be caught in the blades of the fan!
Screenwash fluid
Top up to the required level when necessary.
Fluid specification
The fluid must be topped up with a ready-to-use
mixture.
In winter (temperatures below zero), a liquid
containing an agent to prevent freezing must
be used which is appropriate for the prevailing
conditions, in order to protect the elements of the
system (pump, tank, ducts, jets, etc.).
Filling with pure water is prohibited under
all circumstances (risk of freezing,
limestone deposits, etc.).
Diesel fuel additive (Diesel
with particle filter)
On reaching the minimum level in the particle filter additive tank, this warning
lamp comes on fixed, accompanied by an
audible warning and a message warning that the
additive level is too low.
Topping up
This additive must be topped up without delay by
a CITROËN dealer or a qualified workshop.
AdBlue (BlueHDi)
An alert is triggered when the reserve level is
reached.
For more information on the AdBlue range
indicators, refer to the corresponding section.
To avoid the vehicle being immobilised in
accordance with regulations, you must top up the
AdBlue tank.
For more information on the Supply of AdBlue,
refer to the corresponding section.
Checks
Unless otherwise indicated, check these
components in accordance with the
manufacturer's service schedule and according
to your engine.
Otherwise, have them checked by a CITROËN
dealer or a qualified workshop.
Only use products recommended by
CITROËN or products of equivalent
quality and specification.
In order to optimise the operation of
components as important as those in the
braking system, CITROËN selects and offers
very specific products.
12 V battery
The battery does not require any maintenance.
However, check regularly that the terminals
are correctly tightened (versions without quick
release terminals) and that the connections are
clean.

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Practical information
For more information on the precautions
to take before any work on the 12 V battery, refer to the corresponding section.
Versions equipped with Stop & Start are fitted with a 12 V lead-acid battery of specific technology and specification.
Its replacement should be carried out only by
a CITROËN dealer or a qualified workshop.
Passenger compartment
filter
Depending on the environment and the use of the vehicle (e.g. dusty atmosphere,
city driving), change it twice as often, if
necessary .
A clogged passenger compartment filter
can adversely affect air conditioning
system performance and generate
undesirable odours.
Air filter
Depending on the environment and the use of the vehicle (e.g. dusty atmosphere,
city driving), change it twice as often, if
necessary .
Oil filter
Change the oil filter each time the engine oil is changed.
Particle filter (Diesel)
When the particle filter is approaching saturation, this warning lamp comes on
temporarily, accompanied by a message warning
of the risk of filter clogging.
As soon as the traffic conditions permit,
regenerate the filter by driving at a speed of at
least 37 mph (60 km/h) until the warning lamp goes off.
If the warning lamp stays on, this
indicates a low Diesel additive level.
For more information on Checking levels,
refer to the corresponding section.
Following prolonged operation of the
vehicle at very low speed or at idle, you
may, in exceptional circumstances, notice the
emission of water vapour at the exhaust while
accelerating. This has no impact on the
vehicle’s behaviour or the environment.
New vehicle
During the first few particle filter
regeneration operations, you may notice a
"burning" smell. This is perfectly normal.
Manual gearbox
The gearbox does not require any maintenance (no oil change).
Automatic gearbox
The gearbox does not require any maintenance (no oil change).
Brake pads
Brake wear depends on the style of driving, particularly in the case of vehicles
used in town, over short distances. It may be
necessary to have the condition of the brakes
checked, even between vehicle services.
Unless there is a leak in the circuit, a drop in the
brake fluid level indicates that the brake pads
are worn.
After washing the vehicle, moisture, or in wintry conditions, ice can form on the
brake discs and pads: braking efficiency may
be reduced. Gently dab the brakes to dry and
defrost them.
Brake disc wear
For information on checking brake disc
wear, contact a CITROËN dealer or a
qualified workshop.
Manual parking brake
If you notice excessive brake lever travel or decreased effectiveness, the parking
brake must be adjusted, even between two
services.
This system must be checked by a CITROËN
dealer or a qualified workshop.
Wheels and tyres
The inflation pressure of all tyres, including the spare wheel, must be
checked on "cold” tyres.
The pressures indicated on the tyre pressure
label are valid for "cold" tyres. If you have driven
for more than 10 minutes or more than 6 miles
(10 kilometres) at over 31 mph (50 km/h), add 0.3 bar (30 kPa) to the values indicated on the
label.
Under-inflation increases fuel
consumption. Non-compliant tyre
pressure causes premature wear on tyres and
has an adverse effect on the vehicle's road
holding - risk of an accident!
Driving with worn or damaged tyres reduces the
braking and road holding performance of the
vehicle. It is recommended to regularly check the
condition of the tyres (tread and sidewalls) and
wheel rims as well as the presence of the valves.
When the wear indicators no longer appear set
back from the tread, the depth of the grooves is
less than 1.6 mm; it is imperative to replace the
tyres.
Using different size wheels and tyres from those
specified can affect the lifetime of tyres, wheel
rotation, ground clearance, the speedometer
reading and have an adverse effect on road
holding.
Fitting different tyres on the front and rear axles
can cause the ESC to mistime.

135
Practical information
7Wheels and tyres
The inflation pressure of all tyres, including the spare wheel, must be
checked on "cold” tyres.
The pressures indicated on the tyre pressure
label are valid for "cold" tyres. If you have driven
for more than 10 minutes or more than 6 miles
(10 kilometres) at over 31 mph (50 km/h), add 0.3 bar (30 kPa) to the values indicated on the
label.
Under-inflation increases fuel
consumption. Non-compliant tyre
pressure causes premature wear on tyres and
has an adverse effect on the vehicle's road
holding - risk of an accident!
Driving with worn or damaged tyres reduces the
braking and road holding performance of the
vehicle. It is recommended to regularly check the
condition of the tyres (tread and sidewalls) and
wheel rims as well as the presence of the valves.
When the wear indicators no longer appear set
back from the tread, the depth of the grooves is
less than 1.6 mm; it is imperative to replace the
tyres.
Using different size wheels and tyres from those
specified can affect the lifetime of tyres, wheel
rotation, ground clearance, the speedometer
reading and have an adverse effect on road
holding.
Fitting different tyres on the front and rear axles
can cause the ESC to mistime.
AdBlue® (BlueHDi)

To respect the environment and ensure
compliance with the Euro 6 standard, without
adversely affecting the performance or fuel
consumption of its Diesel engines, CITROËN
has taken the decision to equip its vehicles
with a system that associates SCR (Selective
Catalytic Reduction) with a Diesel Particle Filter
(DPF) for the treatment of exhaust gases.
SCR System
Using a liquid called AdBlue® that contains
urea, a catalytic converter turns up to 85% of
the nitrogen oxides (NOx) into nitrogen and
water, which are harmless to health and the
environment.
The AdBlue® is contained in a special
tank holding about 17 litres.
Its capacity allows a driving range of
approximately 5,600 miles (9,000 km), which
may vary considerably depending on your
driving style.
An alert system is triggered once the reserve
level is reached: it is then possible to drive for a
further 1,500 miles (2,400 km) before the tank is empty and the vehicle blocked.
If the estimated distance travelled by the vehicle
between two services is greater than 12,500
miles (20,000 km), it will be necessary to top up
the AdBlue.
For more information on the Warning
and indicator lamps and the associated
alerts, or the Indicators, please refer to the
corresponding sections.
Once the AdBlue® tank is empty, a
system required by legislation prevents
starting of the engine.
If the SCR system is faulty, the level of
emissions from the vehicle will no longer meet
the Euro 6 standard: the vehicle becomes
polluting.
In the event of a confirmed SCR system
malfunction, it is essential to visit a CITROËN
dealer or a qualified workshop. After 680
miles (1,100 km), a device is automatically
activated to prevent the engine from starting.
In both cases, a range indicator indicates
the distance that can be travelled before the
vehicle is stopped.

136
Practical information
Freezing of the AdBlue®
AdBlue® freezes at temperatures below
around -11°C.
The SCR system includes a heater for the
AdBlue
® tank, allowing you to continue driving
in very cold conditions.
Supply of AdBlue®
It is recommended that the AdBlue® be topped
up as soon as the first alert is issued indicating
that the reserve level has been reached.
For the correct operation of the SCR
system:
– Use only AdBlue® fluid that meets the ISO
22241 standard.
– Never transfer AdBlue® to another container
as it would lose its purity.
– Never dilute AdBlue® with water.
It is possible to obtain AdBlue
® from a CITROËN
dealer or a qualified workshop.
You can also visit a service station equipped with AdBlue® pumps specially
designed for passenger vehicles.
Never top up from an AdBlue® dispenser
reserved for heavy goods vehicles.
Recommendations on storage
AdBlue® freezes at about -11°C and deteriorates
above +25°C. Containers should be stored in a
cool area and protected from direct sunlight.
Under these conditions, the fluid can be kept for
at least a year.
If the fluid has frozen, it can be used once it has
completely thawed out at room temperature.
Never store AdBlue® containers in your
vehicle.
Precautions for use
AdBlue® is a urea-based solution. This fluid is
non-flammable, colourless and odourless (when
kept in a cool place).
In the event of contact with the skin, wash the
affected area with soap and running water. In the
event of contact with the eyes, immediately rinse
the eyes with large amounts of water or with an
eye wash solution for at least 15 minutes. Seek
medical attention if you feel a persistent burning
sensation or irritation.
If swallowed, immediately wash out the mouth
with clean water and then drink plenty of water.
In certain conditions (high temperature, for
example), the risk of release of ammonia cannot
be excluded: do not inhale the fluid. Ammonia
vapours have an irritant effect on mucous
membranes (eyes, nose and throat).
Store AdBlue® out of the reach of
children, in its original container.
Procedure
Before starting the top-up procedure, ensure that
the vehicle is parked on a flat and level surface.
In wintry conditions, ensure that the temperature
of the vehicle is above -11 °C. Otherwise, the AdBlue® may be frozen and therefore cannot
be poured into its tank. Park your vehicle in a
warmer area for a few hours to allow the top-up
to be carried out.
Never pour AdBlue® into the Diesel fuel
tank.
If any AdBlue® is splashed, or if there are
any spillages on the bodywork, rinse
immediately with cold water or wipe with a
damp cloth.
If the fluid has crystallised, clean it off using a
sponge and hot water.
Important: in the event of a top-up after
a breakdown because of a lack of
AdBlue, it is essential to wait around 5
minutes before switching on the ignition,
without opening the driver’s door,
unlocking the vehicle, introducing the key
into the ignition switch, or introducing the
key of the “Keyless Entry and Starting ” system into the passenger compartment .
Switch on the ignition, then wait for 10
seconds before starting the engine.
► Switch off the ignition and remove the key from the switch to switch off the engine.
or
► With Keyless Entry and Starting, press the "START/STOP" button to switch off the engine.

► With the vehicle unlocked and the fuel filler flap open, turn the blue cap of the AdBlue® tank
a quarter turn anti-clockwise.
Filling up
► With a container of AdBlue®: after checking
the expiry date, read the instructions on the
label carefully before pouring the contents of the
container into the vehicle's AdBlue tank.► With an AdBlue® pump: introduce the nozzle
and fill the tank until the nozzle automatically
cuts out.
In order not to overfill the AdBlue® tank:
– Add between 10 and 13 litres using AdBlue® containers.

137
Practical information
7► Switch off the ignition and remove the key from the switch to switch off the engine.
or
► With Keyless Entry and Starting, press the "START/STOP" button to switch off the engine.

► With the vehicle unlocked and the fuel filler flap open, turn the blue cap of the AdBlue® tank
a quarter turn anti-clockwise.
Filling up
► With a container of AdBlue®: after checking
the expiry date, read the instructions on the
label carefully before pouring the contents of the
container into the vehicle's AdBlue tank.► With an AdBlue® pump: introduce the nozzle
and fill the tank until the nozzle automatically
cuts out.
In order not to overfill the AdBlue® tank:
– Add between 10 and 13 litres using AdBlue® containers.
– Stop after the nozzle’ s first automatic cut-out, if you are refilling at a service station.
The system only registers AdBlue® top-ups of 5 litres or more.
If the AdBlue® tank is completely empty
– which is confirmed by the message
"Top up AdBlue: Starting impossible" – it is essential to add at least 5 litres.
After refilling
► Perform the same sequence of operations in reverse order.
Do not dispose of AdBlue® containers in
the household waste.
Place them in a container reserved for this
purpose or take them back to where you
purchased them.
Advice on care and
maintenance
General recommendations
Observe the following recommendations to avoid
damaging your vehicle.
Exterior
Never use a high-pressure jet wash in
the engine compartment, due to the risk
of damaging electrical components.
Do not wash the vehicle in strong sunshine or
extremely cold conditions.
When washing the vehicle at an
automatic roller-brush car wash, be sure
to lock the doors and, depending on version,
remove the electronic key and deactivate the
“hands-free” function (“Hands-Free Tailgate
Access”).
When using a pressure washer, hold the
lance at least 30 cm from the vehicle
(particularly when cleaning areas containing
chipped paint, sensors or seals).
Promptly clean up any stains containing
chemicals liable to damage the vehicle's paint
(including tree resin, bird droppings, insect
secretions, pollen and tar).
If justified by the environment, clean the
vehicle more frequently to remove salty
deposits (in coastal areas), soot (in industrial
estates) and mud (in wet or cold areas).
These substances can be highly corrosive.
Contact a CITROËN dealer or a qualified
workshop if you require advice on removing
stubborn stains requiring special products
(such as tar or insect removers).

146
In the event of a breakdown
Refitting the lamp unitsPerform the operations in the reverse
order to dismantling.
Opening the bonnet / Accessing the
bulbs
With the engine warm, proceed with caution -
risk of burns!
Take care with objects or clothing that could
be caught in the blades of the cooling fan -
risk of strangulation!
Halogen bulbs (Hx)To ensure good quality lighting, check
that the bulb is correctly positioned in its
housing.
Light-emitting diode (LED)
headlamps and lamps
Depending on version, the affected types of
headlamps / lamps are:
– Daytime running lamps / sidelamps.– Direction indicator side repeaters.– Third brake lamp.– Number plate lamps.
Putting the spare wheel
back in place
The punctured wheel cannot be placed in
the boot under the floor.


► Put the spare wheel back in place in its housing.► Slacken the nut on the bolt by a few turns.► Position the fastening device (nut and bolt) in the middle of the wheel.► Tighten the central nut sufficiently to retain the wheel correctly.► Put the tool box back in place in the middle of the wheel and clip it in place.► Clip the tool storage box or put the polystyrene cover back in place (depending on
version).
If there is no wheel in the well, the
fastening device (nut and bolt) cannot be
refitted.
After changing a wheel

With a "space-saver" type spare wheel
Deactivate certain driving aid functions
(Active Safety Brake, Adaptive cruise control,
etc.).
Do not exceed the maximum authorised
speed of 50 mph (80 km/h).Driving with more than one “space-saver”
type spare wheel is prohibited.
Visit a CITROËN dealer or a qualified
workshop as soon as possible to have
the tightness of the bolts and the pressure of
the spare wheel checked.
Have the punctured tyre examined. After
inspection, the technician will advise you on
whether the tyre can be repaired or if it must
be replaced.
Changing a bulb
In some weather conditions (e.g. low
temperature or humidity), misting on the
internal surface of the glass of the headlamps
and rear lamps is normal, and will disappear
after the lamps have been on for a few
minutes.
The headlamps have polycarbonate lenses with a protective coating:
– Do not clean them with a dry or abrasive
cloth, nor with detergent or solvent
products.
– Use a sponge and soapy water or a pH neutral product.– When using a high-pressure washer on persistent marks, do not keep the lance
directed towards the headlamps, lamps or
their edges for too long, so as not to damage
their protective coating and seals.
Changing a bulb must only be done with
the ignition off and after the headlamp /
lamp has been switched off for several
minutes - risk of serious burns!
Do not touch the bulb directly with your
fingers; use a lint-free cloth.
It is essential only to use anti-ultraviolet
(UV) type bulbs, so as not to damage the
headlamp.
Always replace a failed bulb with a new bulb
of the same type and specification. To avoid
lighting imbalance, replace the bulbs in pairs.

147
In the event of a breakdown
8Refitting the lamp units
Perform the operations in the reverse
order to dismantling.
Opening the bonnet / Accessing the
bulbs
With the engine warm, proceed with caution -
risk of burns!
Take care with objects or clothing that could
be caught in the blades of the cooling fan -
risk of strangulation!
Halogen bulbs (Hx)
To ensure good quality lighting, check
that the bulb is correctly positioned in its
housing.
Light-emitting diode (LED)
headlamps and lamps
Depending on version, the affected types of
headlamps / lamps are:
– Daytime running lamps / sidelamps.– Direction indicator side repeaters.– Third brake lamp.– Number plate lamps.
For the replacement of this type of bulb,
you must contact a CITROËN dealer or a
qualified workshop.
Do not touch the "Full LED" technology
headlamps - risk of electrocution!
Front lamps
1. Daytime running lamps / Sidelamps (W21/5W
or LED)
2. Direction indicators (PY21W)
3. Dipped beam headlamps (H7)
4. Main beam headlamps (H7)
5. Foglamps (H8)
Daytime running lamps / sidelamps

► Turn the bulb holder an eighth of a turn anti-clockwise and remove it.► Remove the bulb and replace it.
Direction indicators

Rapid flashing of a direction indicator
lamp (left or right) indicates that one of

153
In the event of a breakdown
8Protect your eyes and face before
handling the battery.
All operations on the battery must be carried
out in a well ventilated area and away from
naked flames and sources of sparks, so as to
avoid the risk of explosion or fire.
Wash your hands afterwards.
Access to the battery
The battery is located under the bonnet.

For access to the (+) terminal:► unlock the bonnet by activating the internal command, then the external command.► lift the bonnet, then fix it in place with its rod.(+) Positive terminal.
It has a quick-release clamp.
(-) Negative terminal.
The battery (-) terminal is not accessible, use the
engine mounting.
Starting using another
battery
When your vehicle's battery is discharged, the
engine can be started using a backup battery
(external or from another vehicle) and jump
leads or a battery booster.
Never try to start the engine by
connecting a battery charger.
Never use a 24 V or higher battery booster.
Check beforehand that the backup battery
has a nominal voltage of 12 V and a capacity
at least equal to that of the discharged
battery.
The two vehicles must not be in contact with
each other.
Switch off all the electrical consumers on both
vehicles (audio system, wipers, lighting, etc.).
Make sure that the jump leads are not close
to moving parts of the engine (fan, belts, etc.).
Do not disconnect the (+) terminal while the
engine is running.


► Lift the plastic cover on the (+) terminal, if your vehicle has one.► Connect the red cable to the positive terminal (+) of flat battery A (at the metal elbow) then to
the positive terminal (+) of backup battery B or
the booster.
► Connect one end of the green or black cable to the negative terminal (-) of backup battery B
or the booster (or an earth point on the other
vehicle).
► Connect the other end of the green or black cable to earth point C on the broken down
vehicle.
► Start the engine of the vehicle with the good battery and leave it running for a few minutes.► Operate the starter on the broken down vehicle and let the engine run.
If the engine does not start straight away, switch
off the ignition and wait a few moments before
trying again.
► Wait until the engine returns to idle then disconnect the jump lead cables in the reverse
order.