engine LEXUS RX450h 2021 Repair Manual

4427-2. Steps to take in an emergency
7Confirm it is not loose after tighten-
ing:
1 Push and pull the tire
2 Try rotating
Visually check to ensure tire is not hung on
surrounding parts.
If looseness or misassembly exists, repeat
steps 2 to 7.
8 Repeat step 7, any time the tire is
lowered or disturbed.
9 Stow the jack and all tools.
■The compact spare tire
●The compact spare tire is identified by the
label “TEMPORARY USE ONLY” on
the tire sidewall. Use the compact spare
tire temporarily, and only in an emer-
gency.
●Make sure to check the tire inflation pres-
sure of the compact spare tire. ( P.466)
■When using the compact spare tire
As the compact spare tire is not equipped
with a tire pressure warning valve and trans-
mitter, low inflation pressure of the spare
tire will not be indicated by the tire pressure
warning system. Also, if you replace the
compact spare tire after the tire pressure
warning light comes on, the light remains
on.
■When the compact spare tire is
equipped
When driving with the compact spare tire
installed, the vehicle he ight will be different
than when driving with standard tires.
■If you have a flat front tire on a road cov-
ered with snow or ice
Install the compact spare tire on one of the
rear wheels of the vehicle. Perform the fol-
lowing steps and fit tire chains to the front
tires:
1 Replace a rear tire with the compact
spare tire.
2 Replace the flat front tire with the tire
removed from the rear of the vehicle.
3 Fit tire chains to the front tires.
WARNING
■When using the compact spare tire
●Remember that the compact spare tire
provided is specific ally designed for
use with your vehicle. Do not use your
compact spare tire on another vehicle.
●Do not use more than one compact
spare tire simultaneously.
●Replace the compact spare tire with a
standard tire as soon as possible.
●Avoid sudden acceleration, abrupt
steering, sudden br aking and shifting
operations that cause sudden engine
braking.
■When the compact spare tire is
attached
The vehicle speed may not be correctly
detected, and the following systems may
not operate correctly:
• ABS & Brake assist
•VSC
•TRAC
• Trailer Sway Control
•EPS
•VDIM
• Adaptive Variable Suspension System (if equipped)
• Dynamic radar cruise control with full-speed range

4507-2. Steps to take in an emergency
If you have a set of jumper (or booster)
cables and a second vehicle with a
12-volt battery, you can jump start your
vehicle by following the steps below.
1Confirm that the electronic key is
being carried.
When connecting the jumper (or booster)
cables, depending on the situation, the
alarm may activate and doors locked.
( P.76)
2 Open the hood ( P.369) and fuse
box cover. 3
Open the exclusive jump starting
terminal cover.
4 Remove the engine cover.
5 Connect a positive jumper cable clamp to on your vehicle and connect the
clamp on the other end of the positive cab le to on the second vehicle. Then,
Restarting the hybrid system
A
B

4517-2. Steps to take in an emergency
7
When trouble arises
connect a negative cable clamp to on the second vehicle and connect the
clamp at the other end of the negative cable to .
Exclusive jump starting terminal (your vehicle)
Positive (+) battery terminal (second vehicle)
Negative (-) battery terminal (second vehicle)
Solid, stationary, unpainted metallic point away from the exclusive jump starting
terminal and any mo ving parts as shown in the illustration
6 Start the engine of the second vehi-
cle. Increase the engine speed
slightly and maintain at that level for
approximately 5 minutes to
recharge the 12-volt battery of your
vehicle.
7 Open and close any of the doors of
your vehicle with the power switch
off.
8 Maintain the engine speed of the
second vehicle and start the hybrid
system of your vehicle by turning
the power switch to ON mode.
9 Make sure the “READY” indicator
comes on. If the indicator light does
not come on, contact your Lexus
dealer. 10
Once the hybrid system has
started, remove the jumper cables
in the exact reverse order from
which they were connected.
11 Close the exclusive jump starting
terminal cover, and reinstall the fuse
box cover to its original position.
Once the hybrid system starts, have
the vehicle inspected at your Lexus
dealer as soon as possible.
■Starting the hybrid system when the
12-volt battery is discharged
The hybrid system cannot be started by
push-starting.
■To prevent 12-volt battery discharge
●Turn off the headlights and the audio sys-
tem while the hybrid system is off.
●Turn off any unnecessary electrical com-
C
D
A
B
C
D

4547-2. Steps to take in an emergency
“Engine Coolant Temp High Stop in
a Safe Place See Owner’s Manual”
is shown on the multi-information
display
1 Stop the vehicle in a safe place and
turn off the air conditioning system,
and then stop the hybrid system.
2 If you see steam:
Carefully lift the hood after the
steam subsides.
If you do not see steam:
Carefully lift the hood.
3 After the hybrid system has cooled
down sufficiently, inspect the hoses
WARNING
●Make sure to replace the 12-volt bat-
tery with one designed for this vehicle.
Otherwise, hydrogen gas may enter
the vehicle, possibly causing a fire or
explosion.
●After replacing, securely attach the
exhaust hose and exhaust hole plug to
the exhaust hole of the replaced
12-volt battery. If not properly installed,
gases (hydrogen) may leak into the
vehicle interior, and there is the possi-
ble danger of the gas igniting and
exploding.
NOTICE
■When handling jumper cables
When connecting the jumper cables,
ensure that they do not become entan-
gled in the cooling fans or belt.
■To prevent damaging the vehicle
The exclusive jump starting terminal is to
be used when charging the 12-volt bat-
tery from another ve hicle in an emer-
gency. It cannot be used to jump start
another vehicle.
If your vehicle overheats
The following may indicate that
your vehicle is overheating.
 The needle of the engine coolant
temperature gauge ( P.83)
enters the red zone, or a loss of
hybrid system power is experi-
enced. (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 Output power
reduced” is shown on the
multi-information display.
 Steam comes out from under the
hood.
Correction procedures

4557-2. Steps to take in an emergency
7
When trouble arises
and radiator core (radiator) for any
leaks.
Radiator
Cooling fans
If a large amount of coolant leaks, immedi-
ately contact your Lexus dealer.
4The coolant level is satisfactory if it
is between the “FULL” and “LOW”
lines on the reservoir.
Reservoir
“FULL” line
“LOW” line
Radiator cap
5 Add coolant if necessary.
Water can be used in an emergency if coolant is unavailable.
6
Start the hybrid system and turn the
air conditioning system on to check
that the radiator cooling fans oper-
ate and to check for coolant leaks
from the radiator or hoses.
The fans operate when the air conditioning
system is turned on immediately after a
cold start. Confirm that the fans are oper-
ating by checking the fan sound and air
flow. If it is difficult to check these, turn the
air conditioning system on and off repeat-
edly.
(The fans may not oper ate in freezing tem-
peratures.)
7 If the fans are not operating:
Stop the hybrid system immediately
and contact your Lexus dealer.
If the fans are operating:
Have the vehicle inspected at the
nearest Lexus dealer.
8 Check if “Engine Coolant Temp
High Stop in a Safe Place See
Owner's Manual” is shown on the
multi-information display.
If the message does not disappear:
Stop the hybrid system and contact your
Lexus dealer.
If the message is not displayed:
Have the vehicle inspected at the nearest
A
B
A
B
C
D

4567-2. Steps to take in an emergency
Lexus dealer.
If “Hybrid System Overheated Out-
put power reduced” is shown on the
multi-information display
1 Stop the vehicle in a safe place.
2 Stop the hybrid system and care-
fully lift the hood.
3 After the hybrid system has cooled
down, inspect the hoses and radia-
tor core (radiator) for any leaks.
Radiator
Cooling fans
If a large amount of coolant leaks, immedi-
ately contact your Lexus dealer.
4The coolant level is satisfactory if it
is between the “FULL” and “LOW”
lines on the reservoir.
Reservoir
“FULL” line
“LOW” line 5
Add coolant if necessary.
Water can be used in an emergency if
coolant is unavailable.
6Start the hybrid system and check if
“Hybrid System Overheated Out-
put power reduced” is shown on
the multi-information display.
If the message does not disappear:
Stop the hybrid system and contact
your Lexus dealer.
If the message is not displayed:
Have the vehicle inspected at the
nearest Lexus dealer.
A
B
A
B
C
WARNING
■When inspecting under the hood of
your vehicle
Observe the following precautions.
Failure to do so may result in serious
injury such as burns.
●If steam is seen coming from under the
hood, do not open the hood until the
steam has subsided. The engine com-
partment may be very hot.

4577-2. Steps to take in an emergency
7
When trouble arises
1Stop the hybrid system. Shift the
shift lever to P and set the parking
brake.
2 Remove the mud, snow or sand
from around the front wheels.
3 Place wood, stones or some other
material under the front wheels to
help provide traction.
4 Restart the hybrid system.
5 Shift the shift lever to D or R and
release the parking brake. Then,
while exercising caution, depress
the accelerator pedal.
■When it is difficult to free the vehicle
Press to turn off TRAC.
WARNING
●After the hybrid system has been
turned off, check that the “READY”
indicator is off.
When the hybrid system is operating,
the gasoline engine may automatically
start, or the cooling fans may suddenly
operate even if the gasoline engine
stops. Do not touch or approach rotat-
ing parts such as the fans, which may
lead to fingers or cl othing (especially a
tie, a scarf or a muffler) getting caught,
resulting in serious injury.
●Do not loosen the radiator cap and the
coolant reservoir caps while the hybrid
system and radiator are hot.
High temperature steam or coolant
could spray out.
NOTICE
■When adding engine/power control
unit coolant
Add coolant slowly after the hybrid sys-
tem has cooled down sufficiently. Adding
cool coolant to a hot hybrid system too
quickly can cause damage to the hybrid
system.
■To prevent damage to the cooling sys-
tem
Observe the following precautions:
●Avoid contaminating the coolant with
foreign matter (such as sand or dust,
etc.).
●Do not use any coolant additive.
If the vehicle becomes stuck
Carry out the following proce-
dures if the tires spin or the vehicle
becomes stuck in mud, dirt or snow:
Recovering procedure

4618-1. Specifications
8
Vehicle specifications
tion number for your Lexus. It is used in
registering the ownership of your vehi-
cle.
This number is stamped on the top left
of the instrument panel.
On some models, this number is also
stamped under the right-hand front
seat.This number is also on the Certification
Label.
■Engine number
The engine number is stamped on the
engine block as shown.
Engine
Model3.5 L 6-cylinder (2GR-FXS)
Type6-cylinder V type, 4-cycle, gasoline
Bore and stroke3.70  3.27 in. (94.0  83.0 mm)
Displacement210.9 cu. in. (3456 cm3)
Valve clearance (engine cold)Automatic adjustment

4638-1. Specifications
8
Vehicle specifications
■Oil capacity (Drain and refillref-
erence
*)
*: The engine oil capacity is a reference quantity to be used when changing the
engine oil. Warm up the engine and turn
off the hybrid system, wait more than 5
minutes, and check the oil level on the
dipstick.
■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 starting
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. Outside temperature
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 before the W allow for easier
starting of the engine in cold
weather.
• The 20 in 0W-20 indicates the vis- cosity 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 load con-
ditions.
How to read oil container label:
The International Lubricant Specifica-
tion Advisory Committee (ILSAC)
Certification Mark is added to some oil
containers to help you select the oil you
should use.
Lubrication system
With filter
Vehicles with towing pack-
age
5.8 qt. (5.5 L, 4.8 Imp. qt.)
Vehicles without towing
package
5.7 qt. (5.4 L, 4.8 Imp. qt.)
Without fil-
ter5.6 qt. (5.3 L, 4.7 Imp. qt.)
A

4648-1. Specifications
*: The coolant capacity is a reference quantity.If replacement is necessary, contact your Lexus dealer.
Cooling system
Capacity*
Gasoline
engine
RX450h (Vehicles with out towing package)
10.3 qt. (9.8 L, 8.6 Imp. qt.)
RX450h (Vehicles with towing package)
10.7 qt. (10.1 L, 8.9 Imp. qt.)
RX450hL
13.2 qt. (12.5 L, 11 Imp. qt.)
Power con-
trol unit2.0 qt. (1.9 L, 1.7 Imp. qt.)
Coolant type
Use either of the following:
 “Toyota Super Long Life Coolant”
 Similar high-quality ethylene glycol-based non-silicate,
non-amine, non-nitrite, and non-borate coolant with
long-life hybrid orga nic acid technology
Do not use plain water alone.
Ignition system (spark plug)
MakeDENSO FK20HBR8
Gap0.03 in. (0.8 mm)
NOTICE
■Iridium-tipped spark plugs
Use only iridium-tipped spark plugs. Do not adjust the spark plug gap.