2021 LEXUS RX450h Owners Manual

1774-1. Before driving
4
Driving
■GAWR (Gross Axle Weight Rat-
ing)
The maximum allowable gross axle
weight. The gross axle weight is the
load placed on each axle (front and
rear).
Front GAWR
Rear GAWR
■TWR (Trailer Weight Rating)
The maximum allowable gross trailer
weight. The gross trailer weight is the
sum of the trailer weight and the weight
of the cargo in the trailer.
TWR is calculated assuming base vehi-
cle with one driver, one front passen-
ger, towing package (if available), hitch
and hitch systems (if required).
Additional optional equipment, passengers
and cargo in the vehicle will reduce the
trailer weight rating so as not to exceed
GCWR, GVWR and GAWR.
If the gross trailer weight exceeds 3000
lb. (1360 kg), it is recommended to use a
trailer with 2 or more axles.
With brakes
■Unbraked TWR (Unbraked Trailer
Weight Rating)
The trailer weight rating for towing a
trailer without a trailer service brake
system.
Without brakes
■Tongue Weight
The load placed on the trailer hitch ball.
( P.178)
A
B
A
A

1784-1. Before driving
The gross trailer weight must never
exceed 3500 lb. (1585 kg).
 The gross combinat ion weight must
never exceed 9500 lb. (4309 kg).
 The gross vehicle weight must never
exceed the GVWR indicated on the
Certification Label. ( P.460)
 The gross axle weight on each axle
must never exceed the GAWR indi-
cated on the Certification Label.
( P.460)
 If the gross trailer weight is over the
unbraked TWR, trailer service
brakes are required.
 If the gross trailer weight is over
2000 lb. (907 kg), a sway control
device with sufficient capacity is
required.
Confirm that the gross trailer weight,
gross combination weight, gross vehi-
cle weight, gross axle weight and
tongue weight are all within the limits.
■GCWR*
9500 lb. (4309 kg)
■TWR*
3500 lb. (1585 kg)
■Unbraked TWR*
1000 lb. (453 kg)
*: This models meet the tow-vehicle traile- ring requirement of SAE International
per SAE J2807.
 A recommended tongue weight
varies in accordance with the types
of trailers or towing as described
below.
 To ensure the recommended values
shown below, the trailer must be
loaded by referring to the following
instructions.
•Tongue Weight
The gross trailer weight should be distrib-
uted so that the tongue weight is 9% to
11%.
(Tongue weight/Gross trailer weight x 100
= 9% to 11%)
The gross trailer weight , gross axle weight
and tongue weight can be measured with
platform scales found at a highway weigh-
ing station, building supply company,
trucking company, junk yard, etc.
Weight limits
GCWR, TWR and Unbraked
TWR
Trailer Tongue Weight

1794-1. Before driving
4
Driving
Gross trailer weight
Tongue weight
Trailer hitch assemblies have different
weight capacities. Lexus recommends
the use of Lexus hitch/bracket for your
vehicle. For details, contact your Lexus
dealer.
 If you wish to install a trailer hitch,
contact your Lexus dealer.
 Use only a hitch that conforms to
the gross trailer weight requirement
of your vehicle.
 Follow the directions supplied by the
hitch manufacturer.
 Lubricate the hitch ball with a light
coating of grease.
 Remove the hitch ball whenever you
are not towing a trailer. Remove the
trailer hitch if you do not need it.
After removing the hitch, seal any
mounting hole in the vehicle body to
prevent entry of any substances into
the vehicle. Use the correct trailer ball for your
application.
Trailer ball load rating
Matches or exceeds the gross trailer
weight rating of the trailer.
Ball diameter
Matches the size of the trailer coupler.
Most couplers are stamped with the
required trailer ball size.
Hitch
A
B
WARNING
■Hitches
Trailer hitch assemblies have different
weight capacities established by the hitch
manufacturer. Even though the vehicle
may be physically capable of towing a
higher weight, the operator must deter-
mine the maximum weight rating of the
particular hitch assembly and never
exceed the maximum weight rating
specified for the trailer-hitch. Exceeding
the maximum weight rating set by the
trailer-hitch manufacturer can cause an
accident resulting in death or serious
personal injuries.
Selecting trailer ball
Trailer classTypical trailer ball size
IV2 5/16 in.
II and III2 in.
I1 7/8 in.
A
B

1804-1. Before driving
Shank length
Protrudes beyond the bottom of the lock
washer and nut by at least 2 threads.
Shank diameter
Matches the ball mount hole diameter size.
Weight carrying ball position:
44.96 in. (1142 mm)
Hitch receiver pin hole position:
35.94 in. (913 mm)
Use the wire harness stored in the rear
end under body.
■Auto current cut-off function
In case of over current, the auto cut-off
function stops the power flowing to the
trailer lights to prevent damage to the vehi- cle’s electrical system.
This function is activ
ated when the rated
current of any of the following trailer light
circuit components is exceeded:
●Tail lights: maximum 7.8 A
●Stop/turn signal light (right): maximum
4.5 A
●Stop/turn signal light (left): maximum 4.5
A
■When the auto current cut function is
activated
If a trailer light does not come on due to the
activation of the auto current cut function,
the light system will need to be reset.
Follow the reset procedure shown below.
●If a tail light does not come on, turn off the
headlight switch.
●If the right-side stop/turn signal light does
not come on, put the turn signal in the off
position or remove foot from the brake
pedal.
●If the left-side stop/t urn signal light does
not come on, put the turn signal in the off
position or remove foot from the brake
pedal.
If the emergency flashers do not operate,
press the emergency flasher switch to turn
them off.
After the light system is reset, operate the
light switches again to see if the lights oper-
ate normally.
If the lights do not operate normally, have
the vehicle inspected by your Lexus dealer.
Your vehicle will handle differently
when towing a trailer. Help to avoid an
accident, death or se rious injury, keep
the following in mind when towing:
 Speed limits for towing a trailer vary
by state or province. Do not exceed
the posted towing speed limit.
 Lexus recommends that the vehi-
Positions for towing hitch
receiver and hitch ball
Connecting trailer lights
C
D
A
B
Trailer towing tips

1814-1. Before driving
4
Driving
cle-trailer speed limit is 65 mph
(104 km/h) on a flat, straight, dry
road. Do not exceed this limit, the
posted towing speed limit or the
speed limit for your trailer as set
forth in your trailer owner’s manual,
whichever is lowest. Instability of the
towing vehicle-trailer combination
(trailer sway) increases as speed
increases. Exceeding speed limits
may cause loss of control.
 Before starting out, check the trailer
lights, tires and the vehicle-trailer
connections. Recheck after driving
a short distance.
 Practice turning, stopping and
reversing with the trailer attached in
an area away from traffic until you
become accustomed to the feel of
the vehicle-trailer combination.
 Reversing with a tr ailer attached is
difficult and requires practice. Grip
the bottom of the steering wheel
and move your hand to the left to
move the trailer to the left. Move
your hand to the right to move the
trailer to right. (This is generally
opposite to reversing without a
trailer attached.) Avoid sharp or
prolonged turning. Have someone
guide you when reversing to reduce
the risk of an accident.
 As stopping distance is increased
when towing a trailer, vehicle-to
vehicle distance should be
increased. For each 10 mph (16
km/h) of speed, allow at least one
vehicle and trailer length.
 Avoid sudden braking as you may skid, resulting in the trailer jackknif-
ing and a loss of vehicle control. This
is especially true on wet or slippery
surfaces.
 Avoid jerky starts or sudden accel-
eration.
 Avoid jerky steering and sharp
turns, and slow down before making
turn.
 Note that when making a turn, the
trailer wheels will be closer than the
vehicle wheels to the inside of the
turn. Compensate by making a
wider than normal turning radius.
 Slow down before making a turn, in
cross winds, on wet or slippery sur-
faces, etc. Increasing vehicle speed
can destabilize the trailer.
 Take care when passing other vehi-
cles. Passing requires considerable
distance. After pass ing a vehicle, do
not forget the length of your trailer,
and be sure you have plenty of room
before changing lanes.
 To maintain engine braking effi-
ciency and charging system perfor-
mance when using engine braking,
do not put the transmission in D.
( P.191)
 Instability happens more frequently
when descending steep or long
downhill grades. Before descend-
ing, slow down and downshift. Do
not make sudden downshifts while
descending steep or long downhill
grades.
 Avoid holding the brake pedal down
too long or applying the brakes too

1824-1. Before driving
frequently. This could cause the
brakes to overheat and result in
reduced braking efficiency.
 Due to the added load of the trailer,
your vehicle’s engine may overheat
on hot days (at temperatures over
85°F [30°C]) when driving up a
long or steep grade. If the engine
coolant temperature gauge indi-
cates overheating, immediately turn
off the air conditioning (if in use),
pull your vehicle off the road and
stop in a safe spot. ( P.454)
 Always place wheel blocks under
both the vehicle’s and the trailer’s
wheels when parking. Put the trans-
mission in P and apply the parking
brake. Avoid parking on a slope, but
if unavoidable, do so only after per-
forming the following:
1 Apply the brakes and keep them
applied.
2 Have someone place wheel blocks
under both the vehicle’s and trailer’s
wheels.
3 When the wheel blocks are in
place, release the brakes slowly
until the blocks absorb the load.
4 Shift into P and apply the parking
brake.
5 Turn off the hybrid system.
 When restarting after parking on a
slope:
1 With the transmission in P, start the
hybrid system. Be sure to keep the
brake pedal depressed. 2
Shift into a forward gear. If revers-
ing, shift into R.
3 If the parking brake is in manual
mode, release the parking brake.
(P.195)
4 Release the brake pedal, and slowly
pull or back away from the wheel
blocks. Stop and apply the brakes.
5 Have someone retrieve the blocks.

1834-1. Before driving
4
Driving
Dinghy towing
Your vehicle is not designed to be
dinghy towed (with 4 wheels on the
ground) behind a motor home.
NOTICE
■To avoid serious damage to your vehi-
cle
Do not tow your vehicle with the four
wheels on the ground.
■To prevent causing serious damage to
the hybrid transmission and Hybrid
AWD system
Never tow this vehicle with any of the
wheels on the ground. This may cause
serious damage to the hybrid transmis-
sion and AWD system.

1844-2. Driving procedures
4-2.Driving procedures
1Check that the parking brake is set.
2 Check that the shift lever is in P.
3 Firmly depress the brake pedal.
and a message will be displayed on
the multi-information display.
If it is not displayed, the hybrid system can-
not be started.
4 Press the power switch shortly and
firmly.
When operating the power switch, one
short, firm press is enough. It is not neces-
sary to press and hold the switch.
If the “READY” indicator turns on, the
hybrid system will operate normally.
Continue depressing the brake pedal until
the “READY” indicator is illuminated.
The hybrid system can be started from any
power switch mode.
5Check that the “READY” indicator
is illuminated.
The vehicle will not move when the
“READY” indicator is off.
■Power switch illumination
According to the situation, the power
switch illumination operates as follows.
●When a door is opened, or the power
switch mode is changed from ACCES-
SORY or ON mode to off, the power
switch illumination slowly blinks.
●When depressing the brake pedal with
carrying the electronic key on your per-
son, the power switch illumination rapidly
blinks.
●When the power switch is in ACCES-
SORY or ON mode, the power switch
illumination illuminates.
■If the hybrid system does not start
●The immobilizer system may not have
been deactivated. ( P.73)
Contact your Lexus dealer.
●Check that the shift leve r is securely set in
P. The hybrid system may not start if the
shift lever is displaced out of P. “To Start
Vehicle, Put Shift Lever into P” will be dis-
played on the multi-information display.
●If the door is unlock ed with the mechani-
cal key, the hybrid system cannot be
started using the sm art access system
with push-button start. Refer to P.448to
start the hybrid system. However, if the
electronic key is carried inside the vehicle
and the doors are locked ( P.111), the
hybrid system can be started.
■When the ambient temperature is low,
such as during winter driving conditions
When starting the hybrid system, the flash-
ing time of the “READY” indicator may be
long. Leave the vehicle as it is until the
“READY” indicator is steady on, as steady
means the vehicle is able to move.
■Sounds and vibrations specific to a
hybrid vehicle
 P.67
Power (ignition) switch
Performing the following opera-
tions when carryin g the electronic
key on your person starts the hybrid
system or changes power switch
modes.
Starting the hybrid system