Page 592 of 748

592 7-3. Do-it-yourself maintenance
RX350_U_OM48E90U WA R N I N G ■
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 resultin g 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 been 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 inflation pressure wi thout 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 ar e 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 se alant 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. 585)■
Driving on rough roads
Take particular care when driving on roads with loose surfaces or potholes.
These conditions may cause losses 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.
Page 593 of 748
5937-3. Do-it-yourself maintenance
7
Maintenance and care
RX350_U_OM48E90U The recommended cold tire inflation
pressure and tire size are displayed on
the tire and loading information label.
( P. 6 8 0 )
Tire inflation pressure Tire inflation pressure
Page 594 of 748

594 7-3. Do-it-yourself maintenance
RX350_U_OM48E90U 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
Page 595 of 748

5957-3. Do-it-yourself maintenance
7
Maintenance and care
RX350_U_OM48E90U ■
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 prop erly 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.
Page 596 of 748

596 7-3. Do-it-yourself maintenance
RX350_U_OM48E90U 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 8 5 )Wheels If a wheel is bent, cracked or heavily corroded, it should be replaced. Other-
wise, the tire may separate from the whee l or cause a loss of handling control.
Wheel selection
Aluminum wheel precautions
Page 623 of 748

623
8When trouble arises
RX350_U_OM48E90U 8-1. Essential information
Emergency flashers .................. 624
If your vehicle has to be
stopped in an
emergency................................. 625
8-2. Steps to take in an
emergency
If your vehicle needs to be
towed ........................................... 626
If you think something is
wrong ........................................... 632
Fuel pump shut off
system .......................................... 633
If a warning light turns
on or a warning buzzer
sounds.......................................... 634
If a warning message is
displayed.......................................641
If you have a flat tire................... 646
If the engine will not start ........658
If the shift lever cannot be
shifted from P............................660
If the electronic key does
not operate properly ...............661
If the vehicle battery is
discharged ................................. 665
If your vehicle overheats .........668
If the vehicle becomes
stuck ............................................... 671
Page 632 of 748
632 8-2. Steps to take in an emergency
RX350_U_OM48E90U ●
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 engine ●
Engine missing, stumbling 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 f eeling, pedal almost touches the floorIf you think something is wrong 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
Page 636 of 748

636 8-2. Steps to take in an emergency
RX350_U_OM48E90U (If equipped)
PCS warning light
When the warning light flashes (and a buzzer sounds):
Indicates a malfunction in the PCS (Pre-Collision System)
Have the vehicle inspected by your Lexus dealer immediately.
When the warning light flashes (and a buzzer does not sound):
Indicates that the PCS (Pre-Collision System) is temporarily
unavailable, possibly due to either of the following:
• An area around the radar sensor or camera sensor being dirty,
fogged up or covered with co ndensation, ice, stickers, etc.
Clear the dirt, fog, condensation, ice, stickers, etc.
( P. 2 6 5 , 2 6 6 )
• Radar sensor or camera sensor temperature being outside of its
operational range
Wait for a while until the area around the front sensor has cooled
down sufficiently.
When the warning ligh t is illuminated:
Either the VSC (Vehicle Stability Control) system or PCS (Pre-
Collision System) is disabled or both are disabled.
To enable the PCS, enable both the VSC system and PCS.
( P. 2 74 , 3 7 7 )
Low fuel level warning light
Indicates that remaining fuel is approximately 2.8 gal. (10.8 L,
2.3 Imp. gal.) or less
Refuel the vehicle.
Seat belt reminder light (warning buzzer)
*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.
Tire pressure warning light
Indicates the following:
• Low tire pressure due to flat tire;
• Low tire pressure due to natural causes; or
• The tire pressure warning system is malfunctioning
Immediately stop the vehicle in a safe place.
Handling method ( P. 6 3 8 )
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. 6 4 1Warning light Warning light/Details/Actions