
4596-1. Maintenance and care
6
Maintenance and care
RX450h_U_OM0E013U
■Note for a smart access system with push-button start
●If the door handle becomes wet while the electronic key is within the effective range,
the door may lock and unlock repeatedly. Place the key in a position 6 ft. (2 m) or more
separate from the vehicle while the vehicle is being washed. (Take care to ensure that
the key is not stolen.)
●If the electronic key is inside the vehicle and a door handle becomes wet during a car
wash, a buzzer will sound outside the vehicle. To turn off the alarm, lock all the doors.
●Set the electronic key to battery-saving mode to disable the sm art access system with
push-button start. ( P. 159)
■Aluminum wheels
●Remove any dirt immediately by using a neut ral detergent. Do not use hard brushes or
abrasive cleaners. Do not use stro ng or harsh chemical cleaners.
Use the same mild detergent as used on the paint.
●Do not use detergent on the wheels when they are hot, for example after driving for
long distance in the hot weather.
●Wash detergent from the wheels immediately after use.
■Bumpers
Do not scrub with abrasive cleaners.
■Front side windows water-repellent coating
●The following precautions can extend the effectiveness of the water-repellent coating.
• Remove any dirt, etc. from the front side windows regularly.
• Do not allow dirt and dust to accumulate on the windows for a long period. Clean the windows with a soft, damp cloth as soon as possible.
• Do not use wax or glass cleaners that co ntain abrasives when cleaning the windows.
• Do not use any metallic objects to remove condensation build up.
●When the water-repellent performance has become insufficient, the coating can be
repaired. Contact your Lexus dealer.

4796-3. Do-it-yourself maintenance
6
Maintenance and care
RX450h_U_OM0E013U
The coolant level is satisfactory if it is between the “FULL” and “LOW” lines on
the reservoir when the hybrid system is cold.
■Engine coolant reservoir
Reservoir cap
“FULL” line
“LOW” line
If the level is on or below the “LOW”
line, add coolant up to the “FULL”
line. ( P. 574)
■Power control unit coolant reservoir
Reservoir cap
“FULL” line
“LOW” line
If the level is on or below the “LOW”
line, add coolant up to the “FULL”
line. ( P. 574)
■Coolant selection
Only use “Toyota Super Long Life Coolant” or a similar high quality ethylene glycol
based non-silicate, non-amine, non-nitrite, and non-borate coolant with long-life hybrid
organic acid technology.
U.S.A.:
“Toyota Super Long Life Coolant” is a mixt ure of 50% coolant and 50% deionized water.
(Minimum temperature: -31 F [-35 C])
Canada:
“Toyota Super Long Life Cool ant” is a mixture of 55% coolant and 45% deionized water.
(Minimum temperature: -44 F [-42C])
For more details about coolant, contact your Lexus dealer.
■If the coolant level drops within a short time of replenishing
Visually check the radiator, hoses, engine/power control unit coolant reservoir caps,
drain cock and water pump.
If you cannot find a leak, have your Lexus de aler test the cap and check for leaks in the
cooling system.
Coolant
1
2
3
1
2
3

5256-3. Do-it-yourself maintenance
6
Maintenance and care
RX450h_U_OM0E013U
■LED lights
The headlight low beams, headlight high beams, front turn signal lights (vehicles with tri-
ple-beam headlights), parking lights and daytime running lights, front fog lights, corner-
ing lights (if equipped), front side marker lights (vehicles with tr iple-beam headlights),
side turn signal lights, stop/t ail lights, rear turn signal light (vehicles with triple-beam
headlights), rear side marker lights, high moun ted stoplight, license plate lights, and outer
foot lights consist of a number of LEDs. If any of the LEDs has burned out, take your vehi-
cle to your Lexus dealer to have the light replaced.
■Condensation build-up on the inside of a lens
Temporary condensation build-up on the inside of the headlight lens does not indicate a
malfunction. Contact your Lexus dealer for more information in the following situations:
●Large drops of water have built up on the inside of a lens.
●Water has built up inside a headlight.
■When replacing light bulbs
P. 510
WARNING
■To prevent injury
Before performing any light bulb replacement procedure, be sure to turn the power
switch off. Failure to do so may result in burns from hot components or a part of your
body may get caught on an operating component, possibly causing serious injury.
■Replacing light bulbs
●Turn off the lights. Do not attempt to replac e the bulb immediately after turning off the
lights.
The bulbs become very hot and may cause burns.
●Do not touch the glass portion of the light bulb with bare hands. When it is unavoid-
able to hold the glass portion, use and hold with a clean dry cloth to avoid getting
moisture and oils on the bulb.
Also, if the bulb is scratched or dropped, it may blow out or crack.
●Fully install light bulbs and any parts used to secure them. Failure to do so may result
in heat damage, fire, or water entering th e headlight unit. This may damage the head-
lights or cause condensation to build up on the lens.
●Do not attempt to repair or disassemble th e light bulbs, connectors, electric circuits
or component parts.
Doing so may result in death or se rious injury due to electric shock.
■To prevent damage or fire
●Make sure bulbs are fully seated and locked.
●Check the wattage of the bulb before installing to prevent heat damage.

5387-2. Steps to take in an emergency
RX450h_U_OM0E013U
(If equipped)
PCS warning lightWhen 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 condensation, ice, stickers, etc.
Clear the dirt, fog, condensation, ice, stickers, etc.
( P. 274, 275)
• 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 lig ht 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 bo th the VSC system and PCS.
( P. 283, 384)
Low fuel level warning light
Indicates that remaining fuel is approximately 2.9 gal. (11.0 L,
2.4 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 fastened 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 warnin g system is malfunctioning
Immediately stop the vehicle in a safe place.
Handling method ( P. 540)
Master warning light
A buzzer sounds and the warning light comes on and flashes to
indicate that the master warnin g system has detected a malfunc-
tion.
P. 543
Warning lightWarning light/Details/Actions

5747-2. Steps to take in an emergency
RX450h_U_OM0E013U
■“Engine Coolant Temp High Stop in a Safe Place See Owner’s Manual” is
shown on the multi-information displayStop the vehicle in a safe place and turn off the air conditioning system, and
then stop the hybrid system.
If you see steam:
Carefully lift the hood after the steam subsides.
If you do not see steam:
Carefully lift the hood.
After the hybrid system has
cooled down sufficiently, inspect
the hoses and radiator core (radi-
ator) for any leaks.Radiator
Cooling fans
If a large amount of coolant leaks,
immediately contact your Lexus
dealer.
The coolant level is satisfactory if
it is between the “FULL” and
“LOW” lines on the reservoir.Reservoir
“FULL” line
“LOW” line
Radiator cap
If your vehicle overheats
The following may indicate that your vehicle is overheating.
●The needle of the engine coolant temperature gauge ( P. 97) enters the
red zone, or a loss of hybrid system power is experienced. (For example, the
vehicle speed does not increase.)
●“Engine Coolant Temp High Stop in a Safe Place See Owner’s Manual” or
“Hybrid System Overheated Reduced Output Power” is shown on the
multi-information display.
●Steam comes out from under the hood.
Correction procedures
1
2
3
1
2
4
1
2
3
4

5767-2. Steps to take in an emergency
RX450h_U_OM0E013U
■If “Hybrid System Overheated Reduced Output Power” is shown on the
multi-information displayStop the vehicle in a safe place.
Stop the hybrid system an d carefully lift the hood.
After the hybrid system has
cooled down, inspect the hoses
and radiator core (radiator) for
any leaks. Radiator
Cooling fans
If a large amount of coolant leaks,
immediately contact your Lexus
dealer.
The coolant level is satisfactory if
it is between the “FULL” and
“LOW” lines on the reservoir.Reservoir
“FULL” line
“LOW” line
Add coolant if necessary.
Water can be used in an emergency
if coolant is unavailable.
1
2
3
1
2
4
1
2
3
5

5868-1. Specifications
RX450h_U_OM0E013U
■Engine oil selection
“Toyota Genuine Motor Oil” is used in your Lexus vehicle. Use Lexus
approved “Toyota Genuine Motor Oil” or equivalent to satisfy the following
grade and viscosity.
Oil grade: ILSAC GF-5 multigrade engine oil
Recommended viscosity: SAE 0W-20
SAE 0W-20 is the best choice for
good fuel economy and good start-
ing in cold weather.
If SAE 0W-20 is not available, SAE
5W-20 oil may be used. However, it
must be replaced with SAE 0W-20
at the next oil change.
Oil viscosity (0W-20 is explained here as an example):
• The 0W in 0W-20 indicates the characteristic of the oil which allows cold startability. Oils with a lower value be fore the W allow for easier starting of
the engine in cold weather.
• The 20 in 0W-20 indicates the viscos ity characteristic of the oil when the
oil is at high temperature. An oil with a higher viscosity (one with a higher
value) may be better suited if the vehicle is operated at high speeds, or
under extreme lo ad conditions.
How to read oil container label:
The International Lubricant Specifi-
cation Advisory Committee
(ILSAC) Certification Mark is added
to some oil containers to help you
select the oil you should use.
Outside temperature

5918-1. Specifications
8
Vehicle specifications
RX450h_U_OM0E013U
■Gasoline quality
In very few cases, driveability problems may be caused by th e brand of gasoline you are
using. If driveability problems persist, try ch anging the brand of gasoline. If this does not
correct the problem, consult your Lexus dealer.
■Gasoline quality standards
●Automotive manufacturers in the U.S.A., Europe and Japan have developed a specifi-
cation for fuel quality calle d the World-Wide Fuel Charte r (WWFC), which is expected
to be applied worldwide.
●The WWFC consists of four categories that are based on required emission levels. In
the U.S., category 4 has been adopted.
●The WWFC improves air quality by lowering emissions in vehicle fleets, and improves
customer satisfaction th rough better performance.
■Recommendation of the use of gasoline containing detergent additives
●Lexus recommends the use of gasoline that contains detergent additives to avoid the
build-up of engine deposits.
●All gasoline sold in the U.S.A. contains minimum detergent additives to clean and/or
keep clean intake systems, per EPA’s lowest additives concentration program.
●Lexus strongly recommends the use of Top Tier Detergent Gasoline. For more informa-
tion on Top Tier Detergent Gasoline and a lis t of marketers, please go to the official
website www.toptiergas.com.
Fuel information
You must only use unleaded gasoline.
Select premium unleaded gasoline with an octane rating of 91 (Research
Octane Number 96) or higher required for optimum engine performance.
If 91 octane cannot be obtained, yo u may use unleaded gasoline with an
octane rating as low as 87 (Researc h Octane Number 91). Use of unleaded
gasoline with an octane rating lower than 91 may result in engine knocking
and significantly reduced performance. Persistent knocking can lead to
engine damage and should be correct ed by refueling with higher octane
unleaded gasoline.
At minimum, the gasoline you use should meet the specifications of ASTM
D4814 in the U.S.A.