2003 INFINITI G35 ECU

CHANGING ENGINE COOLANT O Major cooling system repairs should be
performed by your INFINITI retailer. The
service procedures can be found in the
appropriate INFINITI Service Manual. O Improper servicing can result in reduced
heater performance and engine overheat-
ing.
WARNING O To avoid being scalded, never change
the coolant when the engine is hot.
O Never remove the radiator cap when
the engine is hot. Serious burns
could be caused by high pressure
fluid escaping from the radiator.
O Avoid direct skin contact with used
coolant. If skin contact is made, wash
thoroughly with soap or hand cleaner
as soon as possible.
O Keep coolant out of reach of children
and pets.
1. Open radiator drain plug at the bottom of
radiator, and remove radiator filler cap.
O Be careful not to allow coolant to con-
tact drive belts.
O Waste coolant must be disposed of
properly. Check your local regulations.
2. Close the radiator drain plug securely after
the coolant is drained. 3. Fill the radiator slowly with the proper mix-
ture of anti-freeze solution and demineral-
ized water/distilled water. Fill the reservoir
tank up to the MAX level. Then install the
radiator filler cap.
4. Start the engine and warm it up until it
reaches normal operating temperature.
Then race the engine 2 or 3 times under no
load. Watch the engine coolant tempera-
ture gauge for signs of overheating.
5. Stop the engine. After it completely cools
down, refill the radiator up to the filler
opening. Fill the reservoir tank up to the
MAX level. Check the drain plug for any
sign of leakage.
6. Recheck the coolant level after the vehicle
has been driven for a day.SDI0114
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O Check your local regulations.
4. 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 surface
with a clean rag.
Be sure to remove any old rubber gasket
remaining on the mounting surface of
the engine.
6. Coat the gasket on the new filter with clean
engine oil.
7. Screw in the oil filter clockwise until a slight
resistance is felt, then tighten additionally
more than 2/3 turn.
Oil filter tightening torque:
11 to 15 ft-lb
(14.7 to 20.5 N z 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:
22 to 29 ft-lb
(29 to 39 N z m)
Do not use excessive force.
9. Refill engine with recommended oil and
install the cap securely. CAUTION The dipstick must be inserted in place to
prevent oil spillage from the dipstick
hole while filling the engine with oil.
See ªCapacities and recommended fuel/
lubricantsº in the ª9. Technical and con-
sumer informationº section for drain and
refill capacity. The drain and refill capacity
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.
CAUTION When filling oil, do not pull out the
dipstick.
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 10
minutes. Check the oil level with the dip-
stick. Add engine oil if necessary. After the operation 1. Install the engine undercover into position
as the following steps.
a. Pull the center of the small plastic clip out.
b. Hold the engine undercover into position.
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 under-
cover 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 O Prolonged and repeated contact with
used engine oil may cause skin can-
cer.
O 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.
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O Keep the battery surface clean and dry. Any
corrosion should be washed off with a
solution of baking soda and water.
O Make certain the terminal connections are
clean and securely tightened.
O If the vehicle is not to be used for 30 days or
longer, disconnect the (Ð) negative battery
terminal cable to prevent discharging it.
Coupe
CAUTIONWhen the battery cable is removed from
the battery terminal, do not close either
of front doors. The automatic window
adjusting function will not work, and the
side roof panel may be damaged.
To disconnect the negative (þ) battery ter-
minal, perform the procedure in the follow-
ing order. Otherwise, the window and the
side roof panel may contact and be dam-
aged.
1. Close the windows.
2. Open the hood.
3. Close and lock all the doors. 4. Disconnect the negative (þ) battery ter-
minal.
5. Securely close the hood.
To connect the negative (þ) battery termi-
nal, perform the procedure in the following
order. Otherwise, the window and the side
roof panel may contact and be damaged.
1. Unlock and open the driver side door.
Do not close the door.
2. Open the hood.
3. Connect the negative (þ) battery termi-
nal. Then close the hood.
4. Fully open the driver side door window.
5. Close the driver side door and the win-
dow.
Sedan and coupe
WARNING O Do not expose the battery to flames
or electrical sparks. Hydrogen gas
generated by battery action is explo-
sive. 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 you get acid on your eyes,
skin or clothing, immediately flush
with water for at least 15 minutes and
seek medical attention.
O Do not operate the vehicle if the bat-
tery fluid is low. Low battery fluid can
cause a higher load on the battery
which can generate heat, reduce bat-
tery life, and in some cases lead to an
explosion.
O When working on or near a battery,
always wear suitable eye protection
and remove all jewelry.
O Battery posts, terminals and related
accessories contain lead and lead
compounds. Wash hands after han-
dling.
O Keep the battery out of the reach of
children.BATTERY
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unexpectedly.
1. Visually inspect each belt for signs of un-
usual wear, cuts, fraying, oil adhesion or
looseness. If the belt is in poor condition or
loose, have it replaced or adjusted by your
INFINITI retailer.
2. Have the belts checked regularly for condi-
tion and tension in accordance with the
maintenance schedule in this manual.
WARNING Be sure the engine and 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.
REPLACING SPARK PLUGS If replacement is required, see your INFINITI
retailer for servicing.
Platinum-tipped spark plugs It is not necessary to replace the platinum-
tipped spark plugs as frequently as the con-
ventional type spark plugs since they will last
much longer. Follow the maintenance sched-
ule but, do not reuse them by cleaning or
regapping.
Always replace with recommended
platinum-tipped spark plugs. SDI0145
SPARK PLUGS
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Make sure that the ! side faces the
bottom case.
3. Close the lid securely.
4. Push the keyfob button two or three times
to check its operation.
See your INFINITI retailer if you need any
assistance for replacement.
If the battery is removed for any reason
other than replacement, perform step 4
above.
O Be careful not to touch the circuit board
and the battery terminal.
O An improperly disposed battery can
harm the environment. Always confirm
local regulations for battery disposal.
O The keyfob is water-resistant; however,
if it gets wet, immediately wipe it com-
pletely dry.
O When changing batteries, do not let dust
or oil get on the keyfob.
FCC Notice:
Changes or modifications not expressly
approved by the manufacturer compliance
could void the user's authority to operate
the equipment. This device complies with
Part 15 of the FCC Rules and RSS-210 of Industry Canada. Operation is subject to
the following two conditions: (1) This de-
vice may not cause harmful interference,
and (2) this device must accept any inter-
ference received, including interference
that may cause undesired operation of the
device.
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equipped tires, and may not match the
potential maximum vehicle speed. Never
exceed the maximum speed rating of the
tire.
For additional information regarding
tires, refer to ªImportant Tire Safety In-
formationº (US) or ªTire Safety Informa-
tionº (Canada) in the INFINITI Warranty
Information Booklet.
All season tires INFINITI specifies all season tires on some
models to provide good performance for use
all year around, including snowy and icy road
conditions. All season tires are identified by
ALL SEASON and/or M&S on the tire sidewall.
Snow tires have better snow traction than all
season tires and may be more appropriate in
some areas.
Summer tires INFINITI specifies summer tires on some mod-
els to provide superior performance on dry
roads. Summer tire performance in snow and
ice will be substantially reduced. Summer tires
do not have the tire traction rating M&S on the
tire sidewall. If you operate your vehicle in snowy or icy
conditions, INFINITI recommends the use of
snow or all season tires on all four wheels.
Snow tires If snow tires are needed, it is necessary to
select tires equivalent in size and load rating to
the original equipment tires. If you do not, it
can adversely affect the safety and handling of
your vehicle.
Generally, snow tires will have lower speed
ratings than factory equipped tires and may
not match the potential maximum vehicle
speed. Never exceed the maximum speed
rating of the tire.
If you operate your vehicle in snowy or icy
conditions, INFINITI recommends the use of
snow or all season tires on all four wheels.
For additional traction on icy roads, studded
tires may be used. However, some provinces
and states prohibit their use. Check local, state
and provincial laws before installing studded
tires. Skid and traction capabilities of studded
snow tires, on wet or dry surfaces, may be
poorer than that of non-studded snow tires. TIRE CHAINS Use of tire chains may be prohibited according
to location. Check the local laws before install-
ing tire chains. When installing tire chains,
make sure they are of proper size for the tires
on your vehicle and are installed according to
the chain manufacturer's suggestions. Use
only SAE class S chains. Class ªSº chains
are used on vehicles with restricted tire to
vehicle clearance. Vehicles that can use Class
ªSº chains are designed to meet the SAE
standard minimum clearances between the
tire and the closest vehicle suspension or body
component required to accommodate the use
of a winter traction device (tire chains or
cables). The minimum clearances are deter-
mined using the factory equipped tire size.
Other types may damage your vehicle. Use
chain tensioners when recommended by the
tire chain manufacturer to ensure a tight fit.
Loose end links of the tire chain must be
secured or removed to prevent the possibility
of whipping action damage to the fenders or
undercarriage. If possible, avoid fully loading
your vehicle when using tire chains. In addi-
tion, drive at a reduced speed. Otherwise, your
vehicle may be damaged and/or vehicle han-
dling and performance may be adversely af-
fected.
Never install tire chains on a T-type spare
tire. Do not use the chains on dry roads. Do-it-yourself
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EXPLANATION OF MAINTENANCE
ITEMS Additional information on the following
items with ª*º is found in the ª8. Do-it-
yourselfº section.
Outside the vehicle The maintenance items listed here should be
performed from time to time, unless otherwise
specified.
Tires*: Check the pressure with a gauge at
least once a month and always prior to long
distance trips. If necessary, adjust the pres-
sure in all tires, including the spare, to the
specified pressure. Check carefully for dam-
age, cuts or excessive wear.
Wheel nuts*: When checking the tires, make
sure no nuts are missing, and check for any
loose nuts. Tighten if necessary.
Tire rotation*: Tires should be rotated every
7,500 miles (12,000 km) (Sedan).
Tires cannot be rotated (Coupe).
Wheel alignment and balance: If the vehicle
pulls to either side while driving on a straight
and level road, or if you detect uneven or
abnormal tire wear, there may be a need for
wheel alignment. If the steering wheel or seat vibrates at normal
highway speeds, wheel balancing may be
needed.
For additional information regarding tires, refer
to ªImportant Tire Safety Informationº (US) or
ªTire Safety Informationº (Canada) in the
INFINITI Warranty Information booklet.
Windshield: Clean the windshield on a regu-
lar basis. Check the windshield at least every
six months for cracks or other damage. Have a
damaged windshield repaired by a qualified
repair facility.
Windshield wiper blades*: Check for cracks
or wear if they do not wipe properly.
Doors and engine hood: Check that all doors
and the engine hood, operate properly. Also
ensure that all latches lock securely. Lubricate
hinges and latches if necessary. Make sure
that the secondary latch keeps the hood from
opening when the primary latch is released.
When driving in areas using road salt or other
corrosive materials, check lubrication fre-
quently.
Inside the vehicle The maintenance items listed here should be
checked on a regular basis, such as when performing periodic maintenance, cleaning the
vehicle, etc.
Lights*: Clean the headlights on a regular
basis. Make sure that the headlights, stop
lights, tail lights, turn signal lights, and other
lights are all operating properly and installed
securely. Also check headlight aim.
Warning lights and chimes: Make sure that
all warning lights and chimes are operating
properly.
Windshield wiper and washer*: Check that
the wipers and washer operate properly and
that the wipers do not streak.
Windshield defroster: Check that the air
comes out of the defroster outlets properly and
in sufficient quantity when operating the heater
or air conditioner.
Steering wheel: Check for changes in the
steering conditions, such as excessive free
play, hard steering or strange noises.
Seats: Check seat position controls such as
seat adjusters, seatback recliner, etc. to en-
sure they operate smoothly and that all latches
lock securely in every position. Check that the
head restraints move up and down smoothly
and that the locks (if so equipped) hold se-
curely in all latched positions. Maintenance
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Seat belts: Check that all parts of the seat belt
system (For example, buckles, anchors, ad-
justers and retractors) operate properly and
smoothly, and are installed securely. Check
the belt webbing for cuts, fraying, wear or
damage.
Accelerator pedal: Check the pedal for
smooth operation and make sure the pedal
does not catch or require uneven effort. Keep
the floor mat away from the pedal.
Clutch pedal*: Make sure the pedal operates
smoothly and check that it has the proper free
play.
Brakes: Check that the brakes do not pull the
vehicle to one side when applied.
Brake pedal*: Check the pedal for smooth
operation and make sure it has the proper
distance under it when depressed fully. Check
the brake booster function. Be sure to keep the
floor mat away from the pedal.
Parking brake*: Check that the lever has the
proper travel and confirm that your vehicle is
held securely on a fairly steep hill with only the
parking brake applied.
Automatic transmission P (Park) mecha-
nism: On a fairly steep hill check that your
vehicle is held securely with the selector lever in the P (Park) position without applying any
brakes.
Under the hood and vehicle The maintenance items listed here should be
checked periodically (For example, each time
you check the engine oil or refuel).
Windshield washer fluid*: Check that there
is adequate fluid in the tank.
Engine coolant level*: Check the coolant
level when the engine is cold.
Radiator and hoses: Check the front of the
radiator and clean off any dirt, insects, leaves,
etc., that may have accumulated. Make sure
the hoses have no cracks, deformation, dete-
rioration or loose connections.
Brake and clutch fluid level*: Make sure that
the brake and clutch fluid level is between the
MAX and MIN lines on the reservoir.
Battery*: Check the fluid level in each cell.
It should be between the MAX and MIN lines.
Vehicles operated in high temperatures or
under severe conditions require frequent
checks of the battery fluid level.
Engine drive belts*: Make sure that no belt is
frayed, worn, cracked or oily.
Engine oil level*: Check the level after park- ing the vehicle on a level spot and turning off
the engine. (Wait at least 10 minutes for the oil
to drain back into the oil pan.)
Power steering fluid level* and lines: Check
the level when the fluid is cold and the engine
is turned off. Check the lines for proper attach-
ment, leaks, cracks, etc.
Exhaust system: Make sure there are no
loose supports, cracks or holes. If the sound of
the exhaust seems unusual or there is a smell
of exhaust fumes, immediately locate the
trouble and correct it. See ªPrecautions when
starting and drivingº in the ª5. Starting and
drivingº section for exhaust gas (Carbon mon-
oxide).
Underbody: The underbody is frequently ex-
posed to corrosive substances such as those
used on icy roads or to control dust. It is very
important to remove these substances, other-
wise rust will form on the floor pan, frame, fuel
lines and around the exhaust system. At the
end of winter, the underbody should be thor-
oughly flushed with plain water, being careful
to clean those areas where mud and dirt may
accumulate. For additional information, see
ªCleaning exteriorº in the ª7. Appearance and
careº section.
Fluid leaks: Check under the vehicle for fuel,
oil, water or other fluid leaks after the vehicle
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