2021 INFINITI QX80 key battery

8-2Do-it-yourself
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.
. On gasoline engine models, the fuel
filter or fuel lines should be serviced
because the fuel lines are under high
pressure even when the engine is off. It is recommended you visit an
INFINITI retailer for this service.
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.10-35).)
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.
MAINTENANCE PRECAUTIONS

NOTE:
If the extended storage fuse switch mal-
functions or if the fuse is open, it is not
necessary to replace the switch. In this case,
remove the extended storage fuse switch
and replace it with a new fuse of the same
rating.
How to remove the extended storage fuse
switch:
1. To remove the extended storage fuseswitch, be sure the ignition switch is in
the OFF or LOCK position.
2. Be sure the headlight switch is in the OFF position.
3. Remove the fuse box cover.
4. Pinch the locking tabs
found on each
side of the storage fuse switch.
5. Pull the storage fuse switch straight out from the fuse box
.
CAUTION
Be careful not to allow children to
swallow the battery and removed parts.
SDI2451
Replace the battery as follows:
1. Release the lock knob at the back of theIntelligent Key and remove the mechan-
ical key.
2. Insert a small screwdriver into the slit of the corner and twist it to separate the
upper part from the lower part. Use a
Do-it-yourself8-21
INTELLIGENT KEY BATTERY
REPLACEMENT

22,500 Miles/18 Months/36,000
Km
Standard maintenance:.Inspect Intelligent key battery.Replace engine oil and filter.Perform tire rotation
Severe maintenance:
Not Applicable. Proceed to next interval.
25,000 Miles/30 Months/40,000
Km
Standard maintenance:
Not Applicable. Proceed to next interval.
Severe maintenance:
.Inspect brake pads and rotors.Inspect steering gear and linkage.Inspect axle and suspension parts.Inspect propeller shaft (4WD models).Inspect drive shaft boots (4WD models).Inspect exhaust system.Replace engine oil and filter
30,000 Miles/24 Months/48,000
Km
Standard maintenance:.Inspect brake lines and cables.Inspect brake pads and rotors.Inspect fuel tank vapor vent system hoses.Inspect fuel lines/connections.Inspect exhaust system.Inspect steering gear and linkage.Inspect axle and suspension parts.Replace differential gear oil.Inspect propeller shaft (4WD models).Inspect transfer case oil (4WD models).Inspect drive shaft boots (4WD models).Replace engine oil and filter.Replace engine air filter (1).Replace brake fluid.Replace in-cabin microfilter.Perform tire rotation.Lubricate propeller shaft grease (4WD models)
Severe maintenance:
Not Applicable. Proceed to next interval.
(1) If operating mainly in dusty conditions, more
frequent maintenance may be required.
Maintenance and schedules9-9

40,000 Miles/48 Months/64,000
Km
Standard maintenance:
Not Applicable. Proceed to next interval.
Severe maintenance:
.Inspect brake pads and rotors.Inspect steering gear and linkage.Inspect axle and suspension parts.Inspect propeller shaft (4WD models).Inspect drive shaft boots (4WD models).Inspect exhaust system.Replace engine oil and filter.Replace brake fluid.Replace differential gear oil.Replace transfer case oil (4WD models)
45,000 Miles/36 Months/72,000
Km
Standard maintenance:.Inspect brake lines and cables.Inspect brake pads and rotors.Inspect propeller shaft (4WD models).Replace differential gear oil.Inspect transfer case oil (4WD models).Inspect drive shaft boots (4WD models).Replace engine oil and filter.Replace in-cabin microfilter.Replace Intelligent Key battery.Perform tire rotation.Lubricate propeller shaft grease (4WD models)
Severe maintenance:
Not Applicable. Proceed to next interval.
45,000 Miles/54 Months/72,000
Km
Standard maintenance:
Not Applicable. Proceed to next interval.
Severe maintenance:
.Inspect brake pads and rotors.Inspect steering gear and linkage.Inspect axle and suspension parts.Inspect propeller shaft (4WD models).Inspect drive shaft boots (4WD models).Inspect exhaust system.Replace engine oil and filter
Maintenance and schedules9-11

9-14Maintenance and schedules
67,500 Miles/54 Months/108,000
Km
Standard maintenance:.Replace engine oil and filter.Replace Intelligent Key battery.Perform tire rotation
Severe maintenance:
Not Applicable. Proceed to next interval.
70,000 Miles/84 Months/112,000
Km
Standard maintenance:
Not Applicable. Proceed to next interval.
Severe maintenance:
.Inspect brake pads and rotors.Inspect steering gear and linkage.Inspect axle and suspension parts.Inspect propeller shaft (4WD models).Inspect drive shaft boots (4WD models).Inspect exhaust system.Replace engine oil and filter.Replace brake fluid
75,000 Miles/60 Months/120,000
Km
Standard maintenance:.Inspect brake lines and cables.Inspect brake pads and rotors.Inspect engine drive belts.Inspect propeller shaft (4WD models).Replace differential gear oil.Inspect drive shaft boots (4WD models).Inspect transfer case oil (4WD models).Replace engine oil and filter.Replace in-cabin microfilter.Perform tire rotation.Lubricate propeller shaft grease (4WD models)
Severe maintenance:
Not Applicable. Proceed to next interval.

9-16Maintenance and schedules
85,000 Miles/102 Months/
136,000 Km
Standard maintenance:
Not Applicable. Proceed to next interval.
Severe maintenance:
.Inspect brake pads and rotors.Inspect steering gear and linkage.Inspect axle and suspension parts.Inspect propeller shaft (4WD models).Inspect drive shaft boots (4WD models).Inspect exhaust system.Replace engine oil and filter
90,000 Miles/72 Months/144,000
Km
Standard maintenance:.Inspect brake lines and cables.Inspect brake pads and rotors.Inspect engine drive belts.Inspect fuel tank vapor vent system hoses.Inspect fuel lines/connections.Inspect exhaust system.Inspect propeller shaft (4WD models).Inspect steering gear and linkage.Inspect axle and suspension parts.Replace differential gear oil.Inspect transfer case oil (4WD models).Inspect drive shaft boots (4WD models).Replace engine air filter (1).Replace brake fluid.Replace engine oil and filter.Replace in-cabin microfilter.Replace Intelligent Key battery.Perform tire rotation.Lubricate propeller shaft grease (4WD models)
Severe maintenance:
Not Applicable. Proceed to next interval.
(1) If operating mainly in dusty conditions, more
frequent maintenance may be required.
90,000 Miles/108 Months/
144,000 Km
Standard maintenance:
Not Applicable. Proceed to next interval.
Severe maintenance:
.Inspect brake pads and rotors.Inspect steering gear and linkage.Inspect axle and suspension parts.Inspect propeller shaft (4WD models).Inspect drive shaft boots (4WD models).Inspect exhaust system.Replace engine oil and filter.Replace brake fluid

112,500 Miles/90 Months/
180,000 Km
Standard maintenance:.Replace engine oil and filter.Replace Intelligent Key battery.Perform tire rotation
Severe maintenance:
Not Applicable. Proceed to next interval.
115,000 Miles/138 Months/
184,000 Km
Standard maintenance:
Not Applicable. Proceed to next interval.
Severe maintenance:
.Inspect brake pads and rotors.Inspect steering gear and linkage.Inspect axle and suspension parts.Inspect propeller shaft (4WD models).Inspect drive shaft boots (4WD models).Inspect exhaust system.Replace engine oil and filter
120,000 Miles/96 Months/
192,000 Km
Standard maintenance:.Inspect brake lines and cables.Inspect brake pads and rotors.Inspect engine drive belts.Inspect fuel tank vapor vent system hoses.Inspect fuel lines/connections.Inspect exhaust system.Inspect propeller shaft (4WD models).Inspect steering gear and linkage.Inspect axle and suspension parts.Replace differential gear oil.Inspect transfer case oil (4WD models).Inspect drive shaft boots (4WD models).Replace engine air filter (1).Replace brake fluid.Replace engine oil and filter.Replace in-cabin microfilter.Perform tire rotation.Lubricate propeller shaft grease (4WD models)
Severe maintenance:
Not Applicable. Proceed to next interval.
(1) If operating mainly in dusty conditions, more
frequent maintenance may be required.
Maintenance and schedules9-19

11 Index
A
ABS (Anti-lock Braking System) ................... 5-124
Adaptive front lighting system (AFS) ............ 2-45
Advanced air bag system .................................. 1-58
Aiming controlAdaptive front lighting system (AFS) ...... 2-45
Headlights ....................................................... 2-44
Air bag system
Advanced air bag system ............................ 1-58
Front passenger air bag and
status light ....................................................... 1-60
Front-seat mounted side-impact
supplemental air bag system ..................... 1-65
Roof-mounted curtain side-impact and
rollover supplemental air bag system ...... 1-65
Air bag warning labels ....................................... 1-68
Air bag warning light .............................. 1-69, 2-14
Air cleaner housing filter ................................... 8-14
Air conditioner Air conditioner service ................................. 4-37
Air conditioner specification label ......... 10-13
Air conditioning system refrigerant
and oil recommendations ................ 4-37, 10-7
Automatic air conditioner ........................... 4-29
Automatic climate control ......................... 4-28
DUAL mode setting ...................................... 4-32
In-cabin microfilter ........................................ 4-36
Alarm, How to stop alarm (see vehicle
security system) ................................................... 2-35 Alcohol, drugs and driving ................................ 5-10
Antenna .................................................................. 4-37
Anti-lock Braking System (ABS) ................... 5-124
Anti-lock braking system (ABS)
warning light ......................................................... 2-15
Appearance care
Exterior appearance care ............................... 7-2
Interior appearance care ................................ 7-5
Armrest ................................................................... 1-10
Around View
®Monitor ........................................ 4-3
Audible reminders ................................................ 2-19
Auto closure .......................................................... 3-25
Autolight system .................................................. 2-40
Automatic
Automatic air conditioner ........................... 4-29
Automatic Transmission Fluid (ATF) ......... 8-8
Climate control .............................................. 4-28
Door locks .......................................................... 3-6
Drive positioner ............................................. 3-40
Driving with automatic transmission ....... 5-18
Seat positioner .............................................. 3-40
Average speed ...................................................... 2-31
Avoiding collision and rollover ........................... 5-8
B
Back door (See liftgate) ..................................... 3-22
Back-up Collision Intervention
(BCI) system .......................................................... 5-53 Battery .................................................................... 8-11
Battery saver system ........................ 2-44, 2-72
Intelligent Key ................................................. 8-21
Variable voltage control system ............... 8-13
Before starting the engine ................................ 5-15
Belts (See drive belts) ......................................... 8-13
Blind Spot Intervention
®(BSI) system .......... 5-41
Blind Spot Warning (BSW) system ................ 5-31
Booster seats ........................................................ 1-48
Brake
Anti-lock Braking System (ABS) ............ 5-124
Brake booster ................................................. 8-17
Brake fluid ......................................................... 8-9
Brake system ................................................ 5-123
Parking brake operation .............................. 5-22
Warning light .................................................. 2-12
Break-in schedule .............................................. 5-111
Brightness control Instrument panel ............................................ 2-46
Bulb check/instrument panel ........................... 2-12
Bulb replacement ................................................. 8-23
C
Cabin air filter ....................................................... 4-36
Camera aiding sonar function ......................... 4-17
Capacities and
recommended fluids/lubricants ....................... 10-2
Car phone or CB radio ....................................... 4-38
Cargo floor box .................................................... 2-66