2018 LEXUS NX300h battery replacement

671-2. Hybrid system
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For safety and security
Air intake vents
Air discharge vents When a certain level of impact is
detected by the impact sensor, the
emergency shut off system blocks the
high voltage current and stops the fuel
pump to minimize the risk of electrocu-
tion and fuel leakage. If the emergency
shut off system activates, your vehicle
will not restart. To restart the hybrid
system, contact your Lexus dealer.
A message is automatically displayed
when a malfunction occurs in the
hybrid system or an improper opera-
tion is attempted.
If a warning message is shown on the
multi-information display, read the
message and follow the instructions.NOTICE■
Hybrid battery (traction battery) air
intake and discharge vents●
Do not place objects that will block the
air intake vents. The hybrid battery
(traction battery) may have a reduc-
tion in hybrid battery (traction battery)
output as well as be damaged.
●
Clean the air intake and discharge
vents regularly to prevent the hybrid
battery (traction battery) from over-
heating.
●
Do not get water or foreign materials
in either the air intake and discharge
vents as this may cause a short circuit
and damage the hybrid battery (trac-
tion battery).
●
Do not carry large amounts of water
such as water cooler bottles in the
vehicle. If water spills onto the hybrid
battery (traction battery), the battery
may be damaged.
Have the vehicle inspected by your
Lexus dealer. A
B ●
A filter is installed to the air intake vent.
When the filter re mains noticeably
dirty even after cleaning the air intake
vent, filter cleaning or replacement is
recommended. When cleaning or
replacing the filter, contact your Lexus
dealer.
When “Maintenance Required for
Traction battery cooling parts at your
dealer” is shown on the multi-informa-
tion display, the filter may be clogged.
Have the filter cleaned or replaced at
your Lexus dealer.
Emergency shut off system
Hybrid warning message

2394-5. Using the driving support systems
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Driving performed after remova l and installation
of the 12-volt battery. Perform system ini-
tialization.■
When “Parking Support Brake Mal-
function Visit Your Dealer” is displayed
on the multi-information display, the
PKSB OFF indicator flashes and the
buzzer sounds
The system may not be operating properly.
Have the vehicle inspected by your Lexus
dealer.
When the hybrid system output restric-
tion control or brak e control operates,
the buzzer sounds and a message is
displayed on the multi-information dis-
play to alert the driver. Depending on the situat ion, output restric-
tion control operates to either limit accel-
eration or restrict output as much as
possible.WARNING■
In order for the system to operate
properly
Make sure to observe the following pre-
cautions regard ing the sensors
( → P.231). Failure to observe these pre-
cautions may cause the sensors not to
operate properly, and may result in an
unexpected accident. ●
Do not perform work such as modifi-
cation, disassembly or painting●
Only perform replacements using
genuine parts●
Do not subject the area around the
sensors to any impacts●
Do not damage the sensors, and
always keep them clean
■
Handling the suspension
Do not modify the suspension, as
changes to the height or incline of the
vehicle may prevent the sensors from
correctly detecting obstacles, may cause
the system not operate, or may cause the
system to operate unnecessarily. NOTICE■
Preventing unnecessary operation
In the following situations, turn the Park-
ing Support Brake func tion (for static
objects) OFF. The system may operate
even though there is no possibility of a
collision. ●
A chassis roller, chassis dynamo, free
roller or similar equipment is being
used for an inspection, etc. ●
The vehicle is being loaded onto a ship,
truck or other transport vessel ●
The suspension has been lowered or
tires that have a different size than the
genuine tires are equipped ●
The height of the vehicle has drastically
changed due to the carried load (the
nose tilts up or down). ●
A towing hook is installed
Display and buzzer for hybrid
system output restriction con-
trol and brake control

2574-6. Driving tips
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Driving  Use fluids that are appropriate to
the prevailing outside temperatures. •Engine oil
• Engine/power control unit coolant
•Washer fluid
 Have a service technician inspect
the condition of the 12-volt battery.
 Have the vehicle fitted with four
snow tires or purchase a set of tire
chains for the front tires *
.Ensure that all tires are the same size and
brand, and that chains match the size of the
tires. *
: Tire chains cannot be mounted on the
225/60R18 tires.
Perform the following according to the
driving conditions:
 Do not try to forcibly open a window
or move a wiper that is frozen. Pour
warm water over the frozen area to
melt the ice. Wipe away the water Winter driving tips Carry out the necessary prepara-
tions and inspections before driving
the vehicle in winter. Always drive
the vehicle in a manner appropriate
to the prevailing weather condi-
tions.
Preparation for winter
WARNING
■
Driving with snow tires
Observe the following precautions to
reduce the risk of accidents.
Failure to do so may result in a loss of
vehicle control and cause death or seri-
ous injury.
●
Use tires of the specified size.
●
Maintain the recommended level of air
pressure. ●
Do not drive in excess of 75 mph (120
km/h), regardless of the type of snow
tires being used. ●
Use snow tires on all, not just some
wheels. ■
Driving with tire chains
Observe the following precautions to
reduce the risk of accidents.
Failure to do so may result in the vehicle
being unable to be driven safely, and may
cause death or serious injury. ●
Do not drive in excess of the speed
limit specified for the tire chains being
used, or 30 mph (50 km/h), which-
ever is lower. ●
Avoid driving on bumpy road surfaces
or over potholes. ●
Avoid sudden acceleration, abrupt
steering, sudden br aking and shifting
operations that cause sudden engine
braking. ●
Slow down sufficiently before entering
a curve to ensure that vehicle control is
maintained.
NOTICE■
Repairing or replacing snow tires
Request repairs or replacement of snow
tires from Lexus dealers or legitimate tire
retailers.
This is because the removal and attach-
ment of snow tires affects the operation
of the tire pressure warning valves and
transmitters.
Before driving the vehicle

3196-2. Maintenance
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Maintenance and care 6-2.Maintenance
■
Repair and replacement
It is recommended that genuine Lexus parts
be used for repairs to ensure performance
of each system. If non-Lexus parts are used
in replacement or if a repair shop other than
a Lexus dealer perfor ms repairs, confirm
the warranty coverage. ■
Allow inspection and repairs to be per-
formed by a Lexus dealer●
Lexus technicians are well-trained spe-
cialists and are kept up to date with the
latest service information. They are well
informed about the operation of all sys-
tems on your vehicle.●
Keep a copy of the repa ir order. It proves
that the maintenance that has been per-
formed is under warra nty coverage. If any
problem should arise while your vehicle is
under warranty, your Lexus dealer will
promptly take care of it. General maintenance should be per-
formed on a daily basis. This can be
done by yourself or by a Lexus dealer.
Scheduled maintenance should be
performed at specified intervals
according to the maintenance sched-
ule. For details about ma intenance items and
schedules, refer to the “Warranty and Ser-
vice Guide”, “Owner’s Manual Supple-
ment” or “Scheduled Maintenance”.
■
Resetting the message indicating main-
tenance is required (U.S.A. only)
After the required maintenance is pre-
formed according to the maintenance
schedule, please reset the message.
To reset the message, follow the procedures
described below:
1 Press or of the meter control
switches and select .Maintenance requirements To ensure safe and economical driv-
ing, day-to-day care and regular
maintenance are essential. It is the
owner’s responsibility to perform
regular checks. Lexus recommends
the following maintenance:
WARNING
■
If your vehicle is not properly main-
tained
Improper maintenanc e could result in
serious damage to the vehicle and possi-
ble serious injury or death.
■
Handling of the 12-volt battery
●
Engine exhaust, some of its constitu-
ents, and a wide variety of automobile
components contain or emit chemicals
known to the State of California to
cause cancer and birth defects and
other reproductive harm. Work in a
well ventilated area. ●
Oils, fuels and fluids contained in vehi-
cles as well as waste produced by
component wear contain or emit
chemicals known to the State of Cali-
fornia to cause cancer and birth
defects or other re productive harm.
Avoid exposure and wash any affected
area immediately. ●
12-volt Battery post s, terminals and
related accessories contain lead and
lead compounds which are known to
cause brain damage. Wash your hands
after handling. ( → P.333)
General maintenance
Scheduled maintenance

404 8-1. Specifications
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Spark plug
■
12-volt Battery
■
Charging rates
*
: The fluid capacity is the quantity of reference.
If replacement is necessary, contact your Lexus dealer.Ignition system Make DENSO FK16HR-A8
Gap 0.03 in. (0.8 mm)
NOTICE■
Iridium-tipped spark plugs
Use only iridium-tipped spark plugs. Do not adjust the spark plug gap.
Electrical system Specific voltage reading
at 68°F (20°C): 12.0 V or higher
If the voltage is lower th an the standard value,
charge the battery.
(After charging the battery, turn on the high beam
headlights for 30 seconds with the power switch
off, and turn the headlights off.)
Quick charge
Slow charge 15 A max.
5 A max.
Hybrid transmission Fluid capacity * 
Front
4.0 qt. (3.8 L, 3.3 Imp.qt.)
Fluid type Toyota Genuine ATF WS
NOTICE
■
Transmission fluid type
Using transmission fluid other than “Toyota Genuine ATF WS” may ultimately damage
the hybrid transmission of your vehicle.