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5257-3. Do-it-yourself maintenance
7
Maintenance and care
NX300h_OM_USA_OM78082U
Tire inflation pressure
The recommended cold tire inflation
pressure and tire size are displayed on
the tire and loading information label.
(P. 6 1 3 )
Tire inflation pressure
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5267-3. Do-it-yourself maintenance
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Tire valve
Tire pressure gauge
Remove the tire valve cap.
Press the tip of the tire pressure gauge onto the tire valve.
Read the pressure using the gauge gradations.
If the tire inflation pressure is not at the recommended level, adjust the pres-
sure.
If you add too much air, press the center of the valve to deflate.
After completing the tire inflation pressure measurement and adjustment,
apply soapy water to the valve and check for leakage.
Put the tire valve cap back on.
■Tire inflation pressure check interval
You should check tire inflation pressure ev ery two weeks, or at least once a month.
Do not forget to check the spare.
■Effects of incorrect tire inflation pressure
Driving with incorrect tire inflation pressure may result in the following:
●Reduced fuel economy
●Reduced driving comfort and poor handling
●Reduced tire life due to wear
●Reduced safety
●Damage to the drive train
If a tire needs frequent inflating, ha ve it checked by your Lexus dealer.
Inspection and adjustment procedure
1
2
1
2
3
4
5
6
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5277-3. Do-it-yourself maintenance
7
Maintenance and care
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■Instructions for checking tire inflation pressure
When checking tire inflation pressure, observe the following:
●Check only when the tires are cold.
If your vehicle has been parked for at least 3 hours or has not been driven for more than
1 mile or 1.5 km, you will get an accurate cold tire inflation pressure reading.
●Always use a tire pressure gauge.
It is difficult to judge if a tire is properly inflated based only on its appearance.
●It is normal for the tire inflation pressure to be higher after driving as heat is generated
in the tire. Do not reduce tire inflation pressure after driving.
●Never exceed the vehicle capacity weight.
Passengers and luggage weight should be placed so that the vehicle is balanced.
WA R N I N G
■Proper inflation is critical to save tire performance
Keep your tires properly inflated.
If the tires are not properly inflated, the following conditions may occur which could
lead to an accident resulting in death or serious injury:
●Excessive wear
●Uneven wear
●Poor handling
●Possibility of blowouts result ing from overheated tires
●Air leaking from between tire and wheel
●Wheel deformation and/or tire damage
●Greater possibility of tire damage while driving (due to road hazards, expansion
joints, sharp edges in the road, etc.)
NOTICE
■When inspecting and adjust ing tire inflation pressure
Be sure to put the tire valve caps back on.
If a valve cap is not installed, dirt or moisture may get into the valve and cause an air
leak, resulting in decreased tire inflation pressure.
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5287-3. Do-it-yourself maintenance
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Wheels
When replacing wheels, care should be taken to ensure that they are equivalent
to those removed in load capacity , diameter, rim width and inset
*.
Replacement wheels are available at your Lexus dealer.
*: Conventionally referred to as “offset”.
Lexus does not recommend using the following:
●Wheels of different sizes or types
●Used wheels
●Bent wheels that have been straightened
●Use only Lexus wheel nuts and wrenches designed for use with your alumi-
num wheels.
●When rotating, repairing or changing your tires, check that the wheel nuts are
still tight after driving 1000 miles (1600 km).
●Be careful not to damage the aluminum wheels when using tire chains.
●Use only Lexus genuine balance weights or equivalent and a plastic or rubber
hammer when balancing your wheels.
■When replacing wheels
The wheels of your vehicle are equipped with tire pressure warning valves and transmit-
ters that allow the tire pressure warning system to provide advance warning in the event
of a loss in tire inflation pressure. Whenever wheels are replaced, tire pressure warning
valves and transmitters must be installed. ( P. 5 1 7 , 5 2 9 )
If a wheel is bent, cracked or heavily corroded, it should be replaced. Other-
wise, the tire may separate from the wheel or cause a loss of handling control.
Wheel selection
Aluminum wheel precautions
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555
8When trouble arises
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8-1. Essential informationEmergency flashers .................. 556
If your vehicle has to be stopped in an
emergency................................. 557
8-2. Steps to take in an emergency If your vehicle needs to be towed .....................................558
If you think something is wrong ........................................... 564
If a warning light turns on or a warning buzzer
sounds.......................................... 565
If a warning message is displayed..................................... 572
If you have a flat tire................... 575
If the hybrid system will not start .............................................. 588
If the shift lever cannot be shifted from P............................590
If the electronic key does not operate properly ...................... 591
If the 12-volt battery is discharged ................................. 594
If your vehicle overheats ......... 599
If the vehicle becomes stuck ............................................. 603
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5648-2. Steps to take in an emergency
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If you think something is wrong
●Fluid leaks under the vehicle
(Water dripping from the air co nditioning after use is normal.)
●Flat-looking tires or uneven tire wear
●Engine coolant temperature gauge needle continually points higher than nor-
mal
●Changes in exhaust sound
●Excessive tire squeal when cornering
●Strange noises related to the suspension system
●Pinging or other noises related to the hybrid system
●Engine misfire or misses, st umbling or running roughly
●Appreciable loss of power
●Vehicle pulls heavily to one side when braking
●Vehicle pulls heavily to one side when driving on a level road
●Loss of brake effectiveness, spongy feeling, pedal almost touches the floor
If you notice any of the following symptoms, your vehicle probably needs
adjustment or repair. Contact your Lexus dealer as soon as possible.
Visible symptoms
Audible symptoms
Operational symptoms
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5678-2. Steps to take in an emergency
8
When trouble arises
NX300h_OM_USA_OM78082U
Low fuel level warning lightIndicates that remaining fuel is approximately 2.2 gal. (8.4 L,
1.8 Imp.gal.) or less
Refuel the vehicle.
Driver's and front passenger's seat belt reminder light (warning
buzzer)
*2
Warns the driver and/or front passenger to fasten their seat belts
Fasten the seat belt.
If the front passenger’s seat is occupied, the front passenger’s
seat belt also needs to be fa stened to make the warning light
(warning buzzer) turn off.
Master warning light A buzzer sounds and the warning light comes on and flashes to
indicate that the master warning system has detected a malfunc-
tion.
P. 5 7 2
Tire pressure warning light
When the light comes on:
Low tire inflation pressure such as
• Natural causes ( P. 5 6 9 )
•Flat tire ( P. 5 7 5 )
Adjust the tire inflation pressure to the specified level.
The light will turn off after a fe w minutes. In case the light does
not turn off even if the tire inflation pressure is adjusted, have the
system checked by your Lexus dealer.
When the light comes on after blinking for 1 minute:
Malfunction in the tire pr essure warning system (P. 5 6 9 )
Have the system checked by your Lexus dealer.
*1
Brake Override System/Drive-Start Control warning light
Indicates that:
• The Brake Override System is operating;
• The Brake Override System is malfunctioning (with warning
buzzer);
• The Drive-Start Control is operating (with warning buzzer); or
• The Drive-Start Control is malfunctioning (with warning buzzer)
Follow the instruction that are displayed on the multi-informa-
tion display.
Warning lightWarning light/Details/Actions
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5698-2. Steps to take in an emergency
8
When trouble arises
NX300h_OM_USA_OM78082U
■When the tire pressure warning light comes on
Inspect the appearance of the tire to check that the tire is not punctured.
If the tire is punctured: P. 5 7 5
If the tire is not punctured:
Carry out the following procedure after the tire temperature has lowered sufficiently.
●Check the tire inflation pressure and adjust to the appropriate level.
●If the warning light does not go out even after several minutes, check that the tire infla-
tion pressure is at the specified level and carry out initialization. ( P. 5 1 8 )
The warning light may come on again if the above operations are conducted without first
allowing the tire temperature to lower sufficiently.
■The tire pressure warning light may come on due to natural causes
The tire pressure warning light may come on due to natural causes such as natural air
leaks and tire inflation pressure changes caused by temperature. In this case, adjusting
the tire inflation pressure will turn off the warning light (after a few minutes).
■When a tire is replaced with a spare tire
Vehicles with a compact spare tire: The comp act spare tire is not equipped with a tire
pressure warning valve and transmitter. If a tire goes flat, the tire pressure warning light
will not turn off even though the flat tire ha s been replaced with the spare tire. Replace
the spare tire with the repaired tire and adjust the tire inflation pressure. The tire pressure
warning light will go off after a few minutes.
Vehicles with a full-size spare tire: The spare tire is also equipped with a tire pressure
warning valve and transmitter. The tire pressure warning light will turn on if the tire infla-
tion pressure of the spare tire is low. If a tire goes flat, the tire pressure warning light will
not turn off even though the flat tire has been replaced with the spare tire. Replace the
spare tire with the repaired tire and adjust the tire inflation pressure. The tire pressure
warning light will go off after a few minutes.
■Conditions that the tire pressure warning system may not function properly
P. 5 2 1
■If the tire pressure warning light frequently comes on after blinking for 1 minute
If the tire pressure warning light frequently comes on after blinking for 1 minute when the
power switch is turned to ON mode, ha ve it checked by your Lexus dealer.
■Warning buzzer
In some cases, the buzzer may not be heard due to being in a noisy location or audio
sound.