Ford C-MAX Hybrid (2018 year). Manual — part 54

Coolant Change

At specific mileage intervals, as listed in
the scheduled maintenance information,
the coolant should be changed. Add
prediluted coolant approved to the correct
specification. See Capacities and
Specifications (page 270).

Fail-Safe Cooling

Fail-safe cooling allows you to temporarily
drive your vehicle before any incremental
component damage occurs. The fail-safe
distance depends on ambient
temperature, vehicle load and terrain.

How Fail-Safe Cooling Works

If the engine begins to overheat, the
coolant temperature gauge moves toward
the red zone:

A warning lamp illuminates and
a message may appear in the
information display.

If the engine reaches a preset
over-temperature condition, the engine
automatically switches to alternating
cylinder operation. Each disabled cylinder
acts as an air pump and cools the engine.

When this occurs, your vehicle still
operates, however:
•

Engine power is limited.

•

The air conditioning system turns off.

Continued operation increases the engine
temperature, causing the engine to
completely shut down. Your steering and
braking effort increases in this situation.

When the engine temperature cools, you
can re-start the engine. Have your vehicle
checked as soon as possible to minimize
engine damage.

When Fail-Safe Mode Is Activated

WARNINGS

Fail-safe mode is for use during
emergencies only. Operate your
vehicle in fail-safe mode only as long

as necessary to bring your vehicle to rest
in a safe location and seek immediate
repairs. When in fail-safe mode, your
vehicle will have limited power, will not be
able to maintain high-speed operation, and
may completely shut down without
warning, potentially losing engine power,
power steering assist, and power brake
assist, which may increase the possibility
of a crash resulting in serious injury.

Never remove the coolant reservoir
cap when the engine is running or
hot.

Your vehicle has limited engine power
when in the fail-safe mode, drive your
vehicle with caution. Your vehicle does not
maintain high-speed operation and the
engine may operate poorly.

Remember that the engine is capable of
automatically shutting down to prevent
engine damage. In this situation:

1.

Pull off the road as soon as safely
possible and switch the engine off.

2. If you are a member of a roadside

assistance program, we recommend
that you contact your roadside
assistance service provider.

3. If this is not possible, wait a short

period for the engine to cool.

4. Check the coolant level. If the coolant

level is at or below the minimum mark,
add prediluted coolant immediately.

5. When the engine temperature cools,

you can re-start the engine. Have your
vehicle checked as soon as possible to
minimize engine damage.

Note: Driving your vehicle without repair
increases the chance of engine damage.

Engine Coolant Temperature
Management

(If Equipped)

WARNING

To reduce the risk of crash and injury,
be prepared that the vehicle speed
may reduce and the vehicle may not

be able to accelerate with full power until
the coolant temperature reduces.

If you tow a trailer with your vehicle, the
engine may temporarily reach a higher
temperature during severe operating
conditions, for example ascending a long
or steep grade in high ambient
temperatures.

At this time, you may notice the coolant
temperature gauge moves toward the red
zone and a message may appear in the
information display.

You may notice a reduction in vehicle
speed caused by reduced engine power in
order to manage the engine coolant
temperature. Your vehicle may enter this
mode if certain high-temperature and
high-load conditions take place. The
amount of speed reduction depends on
vehicle loading, grade and ambient
temperature. If this occurs, there is no need
to pull off the road. You can continue to
drive your vehicle.

The air conditioning may automatically
turn on and off during severe operating
conditions to protect the engine from
overheating. When the coolant
temperature decreases to the normal
operating temperature, the air conditioning
turns on.

If the coolant temperature gauge moves
fully into the red zone, or if the coolant
temperature warning or service engine
soon messages appear in your information
display, do the following:

1.

Pull off the road as soon as safely
possible and shift the transmission into
park (P).

2. Leave the engine running until the

coolant temperature gauge needle
returns to the normal position. If the
temperature does not drop after
several minutes, follow the remaining
steps.

3. Switch the engine off and wait for it to

cool. Check the coolant level.

4. If the coolant level is at or below the

minimum mark, add prediluted coolant
immediately.

5. If the coolant level is normal, restart

the engine and continue.

AUTOMATIC TRANSMISSION
FLUID CHECK

If required, have an authorized dealer check
and change the transmission fluid at the
correct service interval. See Scheduled
Maintenance (page 415).

The automatic transmission does not have
a transmission fluid dipstick. Your
transmission does not consume fluid.

An authorized dealer should check the
fluid:
•

If the transmission is not working
properly.

•

If you notice signs of fluid leakage.

Do not use supplemental transmission
fluid additives, treatments or cleaning
agents. The use of these materials may
affect transmission operation and result
in damage to internal transmission
components.

BRAKE FLUID CHECK

WARNINGS

Do not use any fluid other than the
recommended brake fluid as this will
reduce brake efficiency. Use of

incorrect fluid could result in the loss of
vehicle control, serious personal injury or
death.

Only use brake fluid from a sealed
container. Contamination with dirt,
water, petroleum products or other

materials may result in brake system
damage or failure. Failure to adhere to this
warning could result in the loss of vehicle
control, serious personal injury or death.

Do not allow the fluid to touch your
skin or eyes. If this happens, rinse the
affected areas immediately with

plenty of water and contact your physician.

A fluid level between the MAX and
MIN lines is within the normal
operating range and there is no need

to add fluid. A fluid level not in the normal
operating range could compromise the
performance of the system. Have your
vehicle checked immediately.

To avoid fluid contamination, the reservoir
cap must remain in place and fully tight,
unless you are adding fluid.

Only use fluid that meets Ford
specifications. See Capacities and
Specifications (page 270).

POWER STEERING FLUID
CHECK

Your vehicle is equipped with an electric
power steering (EPS) system. There is no
fluid reservoir to check or fill.

WASHER FLUID CHECK

WARNING

If you operate your vehicle in
temperatures below 41.0°F (5°C),
use washer fluid with antifreeze

protection. Failure to use washer fluid with
antifreeze protection in cold weather could
result in impaired windshield vision and
increase the risk of injury or accident.

Note: The front and rear washer systems
are supplied from the same reservoir.

Add fluid to fill the reservoir if the level is
low. Only use a washer fluid that meets
Ford specifications. See Capacities and
Specifications (page 270).

State or local regulations on volatile
organic compounds may restrict the use
of methanol, a common windshield washer
antifreeze additive. Washer fluids
containing non-methanol antifreeze
agents should be used only if they provide
cold weather protection without damaging
the vehicle’s paint finish, wiper blades or
washer system.

FUEL FILTER

Your vehicle is equipped with a lifetime
fuel filter that is integrated with the fuel
tank. Regular maintenance or replacement
is not needed.

CHANGING THE 12V BATTERY

WARNINGS

Batteries normally produce explosive
gases which can cause personal
injury. Therefore, do not allow

flames, sparks or lighted substances to
come near the battery. When working near
the battery, always shield your face and
protect your eyes. Always provide correct
ventilation.

When lifting a plastic-cased battery,
excessive pressure on the end walls
could cause acid to flow through the

vent caps, resulting in personal injury and
damage to the vehicle or battery. Lift the
battery with a battery carrier or with your
hands on opposite corners.

Keep batteries out of reach of
children. Batteries contain sulfuric
acid. Avoid contact with skin, eyes or

clothing. Shield your eyes when working
near the battery to protect against possible
splashing of acid solution. In case of acid
contact with skin or eyes, flush
immediately with water for a minimum of
15 minutes and get prompt medical
attention. If acid is swallowed, call a
physician immediately.

Battery posts, terminals and related
accessories contain lead and lead
compounds. Wash hands after

handling.

Your vehicle has a Motorcraft®
maintenance-free battery which normally
does not require additional water during
its life of service.

Note: If your vehicle's battery has a cover
or shield, make sure it is reinstalled after the
battery has been cleaned or replaced.

Note: See an authorized dealer for low
voltage battery access, testing, or
replacement.

When a low voltage battery replacement
is necessary, see an authorized dealer to
replace the low voltage battery with a Ford
recommended replacement low voltage
battery that matches the electrical
requirements of the vehicle.

To ensure proper operation of the battery
management system (BMS), do not allow
a technician to connect any electrical
device ground connection directly to the
low voltage battery negative post. A
connection at the low voltage battery
negative post can cause inaccurate
measurements of the battery condition
and potential incorrect system operation.

Note: If a person adds electrical or
electronic accessories or components to the
vehicle, the accessories or components may
adversely affect the low voltage battery
performance and durability and may also
affect the performance of other electrical
systems in the vehicle.

For longer, trouble-free operation, keep the
top of the battery clean and dry. Also,
make certain the battery cables are always
tightly fastened to the battery terminals.

If you see any corrosion on the battery or
terminals, remove the cables from the
terminals and clean with a wire brush. You
can neutralize the acid with a solution of
baking soda and water.

When a battery replacement is required,
the battery should only be replaced with
a Ford recommended replacement battery
that matches the electrical requirements
of the vehicle.

Because your vehicle’s engine is
electronically-controlled by a computer,
some engine control settings are
maintained by power from the low voltage
battery. Some engine computer settings,
like the idle trim and fuel trim strategy,
optimize the driveability and performance
of the engine. Some other computer
settings, like the clock and radio station