2018 INFINITI Q50 ECU

When performing any inspection or main-
tenance work on your vehicle, always take
care to prevent serious accidental injury to
yourself or damage to the vehicle. The
following are general precautions which
should be closely observed.
WARNING
.Park the vehicle on a level surface,
apply the parking brake securely and
block the wheels to prevent the
vehicle from moving. Move the shift
lever to P (Park).
. Be sure the ignition switch is in the
OFF or LOCK position when per-
forming any parts replacement or
repairs.
. Never connect or disconnect the
battery or any transistorized compo-
nent while the ignition switch is in the
ON position.
. Never leave the engine or automatic
transmission related component har-
nesses disconnected while the igni-
tion switch is in the ON position.
. If you must work with the engine
running, keep your hands, clothing,
hair and tools away from moving
fans, belts and any other moving parts.
. It is advisable to secure or remove
any loose clothing and remove any
jewelry, such as rings, watches, etc.
before working on your vehicle.
. Always wear eye protection when-
ever you work on your vehicle.
. If you must run the engine in an
enclosed space such as a garage, be
sure there is proper ventilation for
exhaust gases to escape.
. Never get under the vehicle while it is
supported only by a jack. If it is
necessary to work under the vehicle,
support it with safety stands.
. Keep smoking materials, flame and
sparks away from fuel tank and the
battery.
. Your vehicle is equipped with an
automatic engine cooling fan. It may
come on at any time without warn-
ing, even if the ignition key is in the
OFF position and the engine is not
running. To avoid injury, always dis-
connect the negative battery cable
before working near the fan.
. Because the fuel lines are under high
pressure even when the engine is off,
it is recommended you visit an
INFINITI retailer for service of the fuel filter or fuel lines.
CAUTION
.
Do not work under the hood while the
engine is hot. Turn the engine off and
wait until it cools down.
. Avoid direct contact with used en-
gine oil and coolant. Improperly dis-
posed engine oil, coolant, and/or
other vehicle fluids can damage the
environment. Always conform to lo-
cal regulations for disposal of vehicle
fluid.
This “8. Do-it-yourself” section gives in-
structions regarding only those items which
are relatively easy for an owner to perform.
A genuine INFINITI Service Manual is also
available. (See “Owner’s Manual/Service
Manual order information” (P.10-26).)
You should be aware that incomplete or
improper servicing may result in operating
difficulties or excessive emissions, and could
affect your warranty coverage. If in doubt
about any servicing, it is recommended you
have it done by an INFINITI retailer.
Do-it-yourself8-3
MAINTENANCE PRECAUTIONS

JVM0652X
CHECKING ENGINE COOLANT
LEVEL
Check the coolant level in the reservoir tank
when the engine is running and after it
reaches normal operating temperature. If
the coolant level is below MIN level
, add
coolant up to the MAX level. If the
reservoir tank is empty, check the coolant
level in the radiator when the engine is cold.
If there is insufficient coolant in the radiator,
fill the radiator with coolant up to the filler
cap above the radiator upper hose opening
and also add it to the reservoir tank up to the
MAX level
. Put on the filler cap above the
radiator upper hose and with the reservoir
cap open, start the engine. Run the engine until it reaches normal operating tempera-
ture. Add coolant up to the MAX level
.
Tighten the cap securely after adding engine
coolant.
If the cooling system requires coolant fre-
quently, have it checked. It is recommended
you visit an INFINITI retailer for this
service.
CHANGING ENGINE COOLANT
It is recommended that major cooling system
repairs be performed by an INFINITI retailer.
The service procedures can be found in the
appropriate INFINITI Service Manual.
Improper servicing can result in reduced
heater performance and engine overheat-
ing.
WARNING
. To avoid the danger of being scalded,
never change the coolant when the
engine is hot.
. Never remove the radiator cap when
the engine is hot. Serious burns could
be caused by high pressure fluid
escaping from the radiator.
. Avoid direct skin contact with used
coolant. If skin contact is made, wash
thoroughly with soap or hand cleaner as soon as possible.
. Keep coolant out of reach of children
and pets.
Engine coolant must be disposed of prop-
erly. Check your local regulations.
Do-it-yourself8-7

8-8Do-it-yourself
The engine cooling system is filled at the
factory with a pre-diluted mixture of 50%
BASF Glysantin® G48® and 50% water to
provide year-round anti-freeze and coolant
protection. The anti-freeze solution contains
rust and corrosion inhibitors. Additional
engine cooling system additives are not
necessary.
WARNING
Never remove the radiator cap when the
engine is hot. Wait until the engine and
radiator cool down. Serious burns could
be caused by high pressure fluid escaping
from the radiator. See precautions in “If
your vehicle overheats” (P.6-16) of this
manual.
CAUTION
.Never use any cooling system addi-
tives such as radiator sealer. Addi-
tives may clog the cooling system and
cause damage to the engine, trans-
mission and/or cooling system.
. When adding or replacing coolant, be
sure to use only BASF Glysantin®
G48® or equivalent. BASF Glysan-
tin® G48® is pre-diluted to provide antifreeze protection to −34°F
(−37°C). If additional freeze protec-
tion is needed due to weather where
you operate your vehicle, add BASF
Glysantin® G48® concentrate fol-
lowing the directions on the contain-
er. If an equivalent coolant other than
BASF Glysantin® G48® is used,
follow the coolant manufacture’s in-
structions to maintain minimum anti-
freeze protection to −34°F (−37°C).
The use of other types of coolant
solutions other than BASF Glysan-
tin® G48® or equivalent may da-
mage the engine cooling system.
. The life expectancy of the factory-fill
coolant is 120,000 miles (192,000
km) or 10 years. Mixing any other
type of coolant other than BASF
Glysantin® G48®, or the use of
non-distilled water will reduce the
life expectancy of the factory-fill
coolant. Refer to the “9. Mainte-
nance and schedules” section of this
manual for more details.
JVM0303X
CHECKING ENGINE COOLANT
LEVEL
Check the coolant level in the reservoir when
the engine is running and after it reaches
normal operating temperature. If the coolant
level is below MIN level
, add coolant up to
the MAX level. Tighten the cap securely
after adding engine coolant.
If the cooling system frequently requires
coolant, have it checked. It is recommended
you visit an INFINITI retailer for this
service.
ENGINE COOLING SYSTEM (for
2.0L turbo gasoline engine models)

8-12Do-it-yourself
JVM0667X
2.0L turbo gasoline engine
JVM0428X
2.0L turbo gasoline engine
Engine oil and filter
1. Place a large drain pan under the drainplug.
2. Remove the oil filler cap.
3. Remove the drain plug
with a wrench
and completely drain the oil.
CAUTION
Be careful not to burn yourself, as the
engine oil is hot.
.Waste oil must be disposed of prop-
erly.
.Check your local regulations.
4. (Perform steps 4 to 7 only when the engine oil filter change is needed.)
Loosen the oil filter
with an oil filter
wrench. Remove the oil filter by turning it
by hand.
5. Wipe the engine oil filter mounting sur- face with a clean rag.
CAUTION
Be sure to remove any old rubber gasket
remaining on the mounting surface of
the engine. Failure to do so could lead to engine damage.
6. Coat the gasket on the new filter with clean engine oil.
7. For VR30DDTT engine models: Screw in the oil filter clockwise until a slight
resistance is felt, then tighten addition-
ally more than 2/3 turn.
For 2.0L turbo gasoline engine models:
Securely tighten the oil filter. Do not use
excessive force.
Oil filter tightening torque:
VR30DDTT engine models
11 to 15 ft-lb
(14.7 to 20.6 N·m)
2.0L turbo gasoline engine models 19 ft-lb
(25 N·m)
8. Clean and re-install the drain plug with a new washer. Securely tighten the drain
plug with a wrench.
Drain plug tightening torque:
VR30DDTT engine models22 to 29 ft-lb
(29.4 to 39.2 N·m)
2.0L turbo gasoline engine models 22 ft-lb
(30 N·m)

Do not use excessive force.
9. Refill engine with recommended oil and install the oil filler cap securely.
See “Capacities and recommended
fluids/lubricants” (P.10-2) for drain and
refill capacity. The drain and refill capa-
city depends on the oil temperature and
drain time. Use these specifications for
reference only. Always use the dipstick
to determine the proper amount of oil in
the engine.
10. Start the engine and check for leakage around the drain plug and the oil filter.
Correct as required.
11. Turn the engine off and wait more than 15 minutes. Check the oil level with the
dipstick. Add engine oil if necessary.
After the operation
1. Install the engine undercover into posi-tion as the following steps.
a. Pull the center of the small plastic clip
out.
b. Hold the engine undercover into posi- tion.
c. Insert the clip through the undercover into the hole in the frame, then push
the center of the clip in to lock the clip
in place. d. Install the other bolts that hold the
undercover in place. Be careful not to
strip the bolts or over-tighten them.
2. Lower the vehicle carefully to the ground.
3. Dispose of waste oil and filter properly.
WARNING
. Prolonged and repeated contact with
used engine oil may cause skin cancer.
. Try to avoid direct skin contact with
used oil. If skin contact is made, wash
thoroughly with soap or hand cleaner
as soon as possible.
. Keep used engine oil out of reach of
children. When checking or replacement is required,
we recommend an INFINITI retailer for
servicing.
CAUTION
.
It is recommended that you use only
Genuine NISSAN Matic S ATF. Do
not mix with other fluids.
. Using automatic transmission fluid
other than Genuine NISSAN Matic S
ATF may cause deterioration in dri-
veability and automatic transmission
durability, and may damage the
automatic transmission. Damage
caused by the use of fluid other than
as recommended is not covered by
the INFINITI new vehicle limited
warranty.
Do-it-yourself8-13
AUTOMATIC TRANSMISSION
FLUID (ATF)

8-16Do-it-yourself
.Pre-mix washer fluid concentrates
with water to the manufacturer’s
recommended levels before pouring
the fluid into the window washer
reservoir. Do not use the window
washer reservoir to mix the washer
fluid concentrate and water. .
Keep the battery surface clean and dry.
Clean the battery with a solution of
baking soda and water.
. Make certain the terminal connections
are clean and securely tightened.
. If the vehicle is not to be used for 30 days
or longer, disconnect the negative (−)
battery terminal cable to prevent dis-
charging it.
NOTE:
Care should be taken to avoid situations
that can lead to potential battery discharge
and potential no-start conditions such as:
1. Installation or extended use of electro-
nic accessories that consume battery
power when the engine is not running
(Phone chargers, GPS, DVD players,
etc.)
2. Vehicle is not driven regularly and/or
only driven short distances.
In these cases, the battery may need to be
charged to maintain battery health.
WARNING
. Do not expose the battery to flames
or electrical sparks. Hydrogen gas
generated by the battery is explosive.
Do not allow battery fluid to contact
your skin, eyes, fabrics, or painted surfaces. After touching a battery or
battery cap, do not touch or rub your
eyes. Thoroughly wash your hands. If
the acid contacts your eyes, skin or
clothing, immediately flush with
water for at least 15 minutes and
seek medical attention.
. Do not operate the vehicle if the fluid
in the battery is low. Low battery
fluid can cause a higher load on the
battery which can generate heat,
reduce battery life, and in some cases
lead to an explosion.
. When working on or near a battery,
always wear suitable eye protection
and remove all jewelry.
. Battery posts, terminals and related
accessories contain lead and lead
compounds. Wash hands after hand-
ling.
. Keep the battery out of the reach of
children.
MAIN BATTERY LOCATION
See “Engine compartment check locations”
(P.8-4) for the battery location.
BATTERY

8-20Do-it-yourself
1. Visually inspect each belt for signs ofunusual wear, cuts, fraying or looseness.
If the belt is in poor condition or loose,
have it replaced or adjusted. It is recom-
mended you visit an INFINITI retailer for
this service.
2. Have the belts checked regularly for condition and tension in accordance with
the maintenance schedule shown in the
“9. Maintenance and schedules” section.
WARNING
Be sure the engine and the ignition
switch are off and that the parking
brake is engaged securely.
CAUTION
Be sure to use the correct socket to
remove the spark plugs. An incorrect
socket can damage the spark plugs.
SDI2020
REPLACING SPARK PLUGS
If replacement is required, it is recommended
you visit an INFINITI retailer for this service.
Iridium-tipped spark plugs
It is not necessary to replace the iridium-
tipped spark plugs as frequently as the
conventional type spark plugs since they will
last much longer. Follow the maintenance
schedule shown in the “9. Maintenance and
schedules” section, but do not reuse them by
cleaning or regapping.
Always replace spark plugs with recom-
mended or equivalent ones.
SPARK PLUGS

the lower part.
3. Replace the battery with a new one. Recommended battery:
CR2032 or equivalent
.Do not touch the internal circuit andelectric terminals as it could cause a
malfunction.
.Hold the battery by the edges. Hold-
ing the battery across the contact
points will seriously deplete the sto-
rage capacity.
.Make sure that the + side faces thebottom of the case.
SDI2452
4. Align the tips of the upper and lower
parts, and then push them togetheruntil it is securely closed.
5. Operate the buttons to check its opera- tion.
If you need any assistance for replacement,
it is recommended you visit an INFINITI
retailer for this service.
FCC Notice:
For USA:
This device complies with Part 15 of the
FCC Rules. Operation is subject to the
following two conditions: (1) This device
may not cause harmful interference, and (2)
this device must accept any interference received, including interference that may
cause undesired operation.
NOTE:
Changes or modifications not expressly
approved by the party responsible for
compliance could void the user’s authority
to operate the equipment.
For Canada:
This device complies with Industry Canada
licence-exempt RSS standard(s). Operation
is subject to the following two conditions:
(1) this device may not cause interference,
and (2) this device must accept any inter-
ference, including interference that may
cause undesired operation of the device.
Do-it-yourself8-27