tire LEXUS RX450H 2019 Workshop Manual

6177-3. Do-it-yourself maintenance
7
Maintenance and care
RX450h_RX450hL_U
■Warning performance of the tire pressure warning system
The warning of the tire pressure warning system will change in accordance with the con-
ditions under which it was init ialized. For this reason, the system may give a warning even
if the tire pressure does not reach a low enough level, or if the pressure is higher than the
pressure that was adjusted to when the system was initialized.
■When initialization of the tire pressure warning system has failed
Initialization may take longer to complete if the vehicle is driven on an unpaved road.
When performing initialization, drive on a pa ved road if possible. Depending on the driv-
ing environment and condition of the tires, initialization will be completed in approxi-
mately 10 to 30 minutes. If initialization is not complete after driving approximately 10 to
30 minutes, continue driving for a while.
If the inflation pressure of each tire is not displayed after driving for approximately 1 hour,
perform the following procedure.
●Park the vehicle in a safe place for approxim ately 20 minutes. Then drive straight (with
occasional left and right turns) at appr oximately 25 mph (40 km/h) or more for
approximately 10 to 30 minutes.
However, in the following situations, the tire inflation pressure will not be recorded and
the system will not operate proper ly. Perform initialization again.
●When operating the tire pressure warning reset switch, the tire pressure warning light
does not blink 3 times.
●After performing initia lization, the tire pressure warning light blinks for 1 minute then
stays on while driving.
If the inflation pressure of each tire is still not displayed, have the vehicle inspected by
your Lexus dealer.

6187-3. Do-it-yourself maintenance
RX450h_RX450hL_U
■Certification for tire pressure warning system
Except for vehicles sold in Canada
For vehicles sold in Canada

6197-3. Do-it-yourself maintenance
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Maintenance and care
RX450h_RX450hL_U
WARNING
■When inspecting or replacing tires
Observe the following precautions to prevent accidents.
Failure to do so may cause damage to parts of the drive train as well as dangerous han-
dling characteristics, which may lead to an accident resulting in death or serious injury.
●Do not mix tires of different makes, models or tread patterns.
Also, do not mix tires of remarkably different treadwear.
●Do not use tire sizes other than those recommended by Lexus.
●Do not mix differently constructed tires (radial, bias-belted or bias-ply tires).
●Do not mix summer, all season and snow tires.
●Do not use tires that have be en used on another vehicle.
Do not use tires if you do not know how they were used previously.
●Do not tow if your vehicle has a compact spare tire installed.
■When initializing the tire pressure warning system
Do not initializing tire inflatio n pressure without first adjusting the tire inflation pressure
to the specified level. Otherwise, the tire pressure warning light may not come on even
if the tire inflation pressure is low, or it may come on when the tire inflation pressure is
actually normal.
NOTICE
■Repairing or replacing tires, wheels, tire pressure warning valves, transmitters and
tire valve caps
●When removing or fitting the wheels, tires or the tire pressure warning valves and
transmitters, contact your Lexus dealer as the tire pressure warning valves and trans-
mitters may be damaged if not handled correctly.
●Make sure to install the tire valve caps. If the tire valve caps are not installed, water
could enter the tire pressure warning valves and the tire pressure warning valves
could be bound.
●When replacing tire valve caps, do not use tire valve caps other than those specified.
The cap may become stuck.
■To avoid damage to the tire pressu re warning valves and transmitters
When a tire is repaired with liquid sealants, the tire pressure warning valve and trans-
mitter may not operate properly. If a liquid sealant is used, contact your Lexus dealer or
other qualified service shop as soon as possible. Make sure to replace the tire pressure
warning valve and transmitter when replacing the tire. ( P. 612)
■Driving on rough roads
Take particular care when driving on roads with loose surfaces or potholes.
These conditions may cause lo sses in tire inflation pressure, reducing the cushioning
ability of the tires. In addition, driving on rough roads may cause damage to the tires
themselves, as well as the vehicle’s wheels and body.
■If tire inflation pressure of ea ch tire becomes low while driving
Do not continue driving, or your tires and/or wheels may be ruined.

6207-3. Do-it-yourself maintenance
RX450h_RX450hL_U
The recommended cold tire inflation
pressure and tire size are displayed on
the tire and loading information label.
( P. 717)
Tire inflation pressure
Tire inflation pressure

6217-3. Do-it-yourself maintenance
7
Maintenance and care
RX450h_RX450hL_U
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

6227-3. Do-it-yourself maintenance
RX450h_RX450hL_U
■Instructions for checking tire inflation pressure
When checking tire in flation 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 inflat ion 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.
WARNING
■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 resu lting 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 on 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.

6237-3. Do-it-yourself maintenance
7
Maintenance and care
RX450h_RX450hL_U
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 referre d 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. 612)
Wheels
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

6247-3. Do-it-yourself maintenance
RX450h_RX450hL_U
WARNING
■When replacing wheels
●Do not use wheels that are a different size from those recommended in the Owner’s
Manual, as this may result in a loss of handling control.
●Never use an inner tube in a leaking wheel which is designed for a tubeless tire. Doing
so may result in an accident, causing death or serious injury.
■Use of defective wheels prohibited
Do not use cracked or deformed wheels.
Doing so could cause the tire to leak air du ring driving, possibly causing an accident.
NOTICE
■Replacing tire pressure warning valves and transmitters
●Because tire repair or replacement may affe ct the tire pressure warning valves and
transmitters, make sure to have tires serviced by your Lexus dealer or other qualified
service shop. In addition, ma ke sure to purchase your tire pressure warning valves
and transmitters at your Lexus dealer.
●Ensure that only genuine Lexus wheels are used on your vehicle.
Tire pressure warning valves and transmitte rs may not work properly with non-genu-
ine wheels.
■Selectable Color Trim (if equipped)
●If rattles, noise, or ot her problems occur while
Selectable Color Trim are installed, contact
your Lexus dealer.
●Do not remove or install Selectable Color
Trim yourself, as it may be damaged. Have the
Selectable Color Trim removed and installed
by your Lexus dealer.

651
8When trouble arises
RX450h_RX450hL_U
8-1. Essential informationEmergency flashers .................. 652
If your vehicle has to be stopped in
an emergency .......................... 653
8-2. Steps to take in an emergency
If your vehicle needs to be towed................................ 654
If you think something is wrong ........................................... 659
If a warning light turns on or a warning buzzer
sounds..........................................660
If a warning message is displayed..................................... 667
If you have a flat tire .................. 673
If the hybrid system will
not start .......................................690
If the electronic key does not operate properly ............. 692
If the 12-volt battery is discharged ................................. 695
If your vehicle overheats ......... 702
If the vehicle becomes stuck ............................................. 706

6578-2. Steps to take in an emergency
8
When trouble arises
RX450h_RX450hL_U
■While towing
If the engine is not running, the power assist for the brakes and steering will not function,
marking steering and braking more difficult.
■Wheel nut wrench
Wheel nut wrench is installe d in luggage compartment. ( P. 674)
WARNING
Observe the following precautions.
Failure to do so may result in death or serious injury.
■When towing the vehicle
■While towing
●When towing using cables or chains, avoid sudden starts, etc. which place excessive
stress on the towing eyelets, cables or chains. The towing eyelets, cables or chains
may become damaged, broken debris ma y hit people, and cause serious damage.
●Do not turn the power switch off.
There is a possibility that the steering wheel is locked and cannot be operated.
■Installing towing eyelets to the vehicle
Make sure that towing eyel ets are installed securely.
If not securely installed, towing ey elets may come loose during towing.
Be sure to transport the vehicle with all four
wheels raised off the ground. If the vehicle is
towed with the tires contacting the ground, the
drivetrain or related parts may be damaged,
the vehicle may fly off the truck, or electricity
generated by the operation of the motor may
cause a fire to occur depending on the nature
of the damage or malfunction.