2022 LEXUS RX450h brake

4097-2. Steps to take in an emergency
7
When trouble arises
Fluid leaks under the vehicle
(Water dripping from the air condi-
tioning after use is normal.)
 Flat-looking tires or uneven tire
wear
 Engine coolant temperature gauge
needle continually points higher
than normal
 Changes in exhaust sound
 Excessive tire squeal when corner-
ing
 Strange noises related to the sus-
pension system
 Pinging or other noises related to
the hybrid system
 Engine missing, stumbling or run-
ning 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
feeling, pedal almost touches the
floor
If you think something is
wrong
If you notice any of the following
symptoms, your vehicle probably
needs adjustment or repair. Con-
tact your Lexus dealer as soon as
possible.
Visible symptoms
Audible symptoms
Operational symptoms

4107-2. Steps to take in an emergency
■Brake system warning light
■Brake system warning light
■High coolant temperature warning light* (warning buzzer)
*: This light illuminates on the multi-information display.
If a warning light turns on or a warning buzzer sounds
Calmly perform the followin g actions if any of the warning lights comes on or
flashes. If a light comes on or flashes, bu t then goes off, this does not necessar-
ily indicate a malfunction in the system. However, if this continues to occur,
have the vehicle inspected by your Lexus dealer.
Actions to the warning lights or warning buzzers
Warning lightDetails/Actions
(U.S.A.)
or
(red)
(Canada)
Indicates that:
 The brake fluid level is low; or
 The brake system is malfunctioning
 Immediately stop the vehicle in a safe place and contact your Lexus
dealer. Continuing to drive the vehicle may be dangerous.
Warning lightDetails/Actions
(yellow)
Indicates a malfunction in:
 The regenerative braking system;
 The electronically controlled brake system; or
 The electric parking brake
 Have the vehicle inspected by your Lexus dealer immediately.
Warning lightDetails/Actions
Indicates that the engine coolant temperature is too high
Immediately stop the vehicle in a safe place.
Handling method ( P.446)

4127-2. Steps to take in an emergency
■SRS warning light
■ABS warning light
■Brake Override System warning light/Drive-Start Control warning light*
(warning buzzer)
*: This light illuminates on th e multi-information display.
Warning lightDetails/Actions
Indicates a malfunction in:
The SRS airbag system;
 The front passenger occupant classification system; or
 The seat belt pretensioner system
 Have the vehicle inspected by your Lexus dealer immediately.
Warning lightDetails/Actions
(U.S.A.)
or
(Canada)
Indicates a malfunction in:
The ABS; or
 The brake assist system
 Have the vehicle inspected by your Lexus dealer immediately.
Warning lightDetails/Actions
When a buzzer sounds:
Brake Override System is malfunctioning;
 Drive-Start Control is operating;
 Drive-Start Control is malfunctioning; or
 PKSB (Parking Support Brake) (if equipped) is operating
 Follow the instructions displayed on the multi-information display.
When a buzzer does not sound:
Brake Override System is operating
 Release the accelerator pedal and depress the brake pedal.

4157-2. Steps to take in an emergency
7
When trouble arises
■Intuitive parking assist OFF indicator (warning buzzer)
■RCTA OFF indicator (warning buzzer)
■PKSB OFF indicator (warning buzzer)
Warning lightDetails/Actions
(flashes)
(if equipped)
Indicates a malfunction in the in tuitive parking assist function
 Have the vehicle inspected by your Lexus dealer immediately.
Indicates that the system is temporarily unavailable, possibly due to a
sensor being dirty or covered with ice, etc.
 Follow the instructions displayed on the multi-information display.
( P.254)
Warning lightDetails/Actions
(flashes)
(if equipped)
Indicates a malfunction in the RCTA (Rear Cross Traffic Alert) function
 Have the vehicle inspected by your Lexus dealer immediately.
Indicates that the rear bumper around the radar sensor is covered with
dirt, etc. ( P.246)
 Follow the instructions displayed on the multi-information display.
( P.260)
Warning lightDetails/Actions
(flashes)
(if equipped)
When a buzzer sounds:
Indicates a malfunction in the PKSB (Parking Support Brake) system
 Have the vehicle inspected by your Lexus dealer immediately.
When a buzzer does not sound:
Indicates that the system is temporarily unavailable, possibly due to a
sensor being dirty or covered with ice, etc.
 Follow the instructions displayed on the multi-information display.
( P.270, 420)

4167-2. Steps to take in an emergency
■PCS warning light
■Slip indicator
■Parking brake indicator
Warning lightDetails/Actions
(flashes or illumi-nates)
When a buzzer sounds simultaneously:
Indicates a malfunction has occurred in the PCS (Pre-Collision System).
 Have the vehicle inspected by your Lexus dealer immediately.
When a buzzer does not sound:
The PCS (Pre-Collision System) has become temporarily unavailable,
corrective action may be necessary.
 Follow the instructions displayed on the multi-information display.
( P.216, 422)
If the PCS (Pre-Collision System) or VSC (Vehicle Stability Control)
system is disabled, the PCS warning light will illuminate.
 P.224
Warning lightDetails/Actions
When the warning lig ht is illuminated:
Indicates a malfunction in:
 The VSC system;
 The TRAC system;
 The Trailer Sway Control; or
 The hill-start assist control system;
 Have the vehicle inspected by your Lexus dealer immediately.
When the warning light flashes:
Indicates that the ABS, VSC, TRAC or Trailer Sway Control system is
operating
Warning lightDetails/Actions
(flashes)
(U.S.A.)
or
(flashes)
(Canada)
It is possible that the parking brake is not fully engaged or released
 Operate the parking brake switch once again.
This light comes on when the parking brake is not released. If the light
turns off after the parking brake is fu lly released, the system is operating
normally.

4177-2. Steps to take in an emergency
7
When trouble arises
■Brake hold operated indicator
■Master warning light
■Warning buzzer
In some cases, the bu zzer may not be heard
due to being in a noisy location or audio
sound.
■Front passenger detection sensor, seat
belt reminder and warning buzzer
●If luggage is placed on the front passen-
ger seat, the front passenger detection
sensor may cause the warning light to
flash and the warning buzzer to sound
even if a passenger is not sitting in the
seat.
●If a cushion is placed on the seat, the sen-
sor may not detect a passenger, and the
warning light may not operate properly.
■SRS warning light
This warning light sy stem monitors the
airbag sensor assembly, front impact sen-
sors, side impact sensors (front door), side
impact sensors (rear), driver’s seat position
sensor, driver’s seat be lt buckle switch, front
passenger occupant cl assification system
(ECU and sensors), “AIR BAG ON” indica-
tor light, “AIR BAG OFF” indicator light,
front passenger’s seat belt buckle switch,
driver’s seat belt pretensioner, front passen-
ger’s seat belt pretensioner and force lim-
iter, airbags, interconnecting wiring and
power sources. ( P.30)
■If the malfunction indicator lamp comes
on while driving
First check the following:
●Is the fuel tank empty?
If it is, fill the fuel tank immediately.
●Is the fuel tank cap loose?
If it is, tighten it securely.
The light will go off after several driving
trips.
If the light does not go off even after several
trips, contact your Lexus dealer as soon as
possible.
■Electric power steering system warning
light (warning buzzer)
When the 12-volt battery charge becomes
insufficient or the voltage temporarily
drops, the electric power steering system
warning light may come on and the warning
buzzer may sound.
■When the tire pressure warning light
comes on
Inspect the tires to check if a tire is punc-
tured.
If a tire is punctured: P.424
If none of the tires are punctured:
Turn the power switch off then turn it to ON
mode. Check if the tire pressure warning
light comes on or blinks.
If the tire pressure warning light blinks for
1 minute then stays on
There may be a malfunction in the tire
pressure warning system. Have the vehicle
inspected by your Lexus dealer immedi-
ately.
Warning lightDetails/Actions
(flashes)
Indicates a malfunction in the brake hold system
 Have the vehicle inspected by your Lexus dealer immediately.
Warning lightDetails/Actions
A buzzer sounds and the warning light comes on and flashes to indicate
that the master warning system has detected a malfunction.
P.420

4187-2. Steps to take in an emergency
If the tire pressure warning light comes
on
1 After the temperature of the tires has
lowered sufficiently, check the inflation
pressure of each tire and adjust them to
the specified level.
2 If the warning light does not turn off
even after several minutes have
elapsed, check that the inflation pres-
sure of each tire is at the specified level
and perform initialization. ( P.378)
If the warning light does not turn off several
minutes after the initia lization has been per-
formed, have the vehicle inspected by your
Lexus dealer immediately.
■The tire pressure warning light may
come on due to natural causes
The tire pressure warning light may come
on due to natural causes such as natural air
leaks and tire inflation pressure changes
caused by temperature. In this case, adjust-
ing the tire inflation pressure will turn off the
warning light (after a few minutes).
■When a tire is replaced with a spare tire
The compact spare tire is not equipped with
a tire pressure warning valve and transmit-
ter. If a tire goes flat , the tire pressure warn-
ing light will not turn off even though the flat
tire has been replaced with the spare tire.
Replace the spare tire with the repaired tire
and adjust the tire inflation pressure. The
tire pressure warning light will go off after a
few minutes.
■Conditions that the tire pressure warn-
ing system may not function properly
P.377
■Customization
Some functions can be customized.
(  P.472)
WARNING
■If both the ABS and the brake system
warning lights remain on
Stop your vehicle in a safe place immedi-
ately and contact your Lexus dealer.
The vehicle will become extremely
unstable during br aking, and the ABS
system may fail, which could cause an
accident resulting in death or serious
injury.
■When the electric power steering
system warning light comes on
When the light comes on yellow, the
assist to the power st eering is restricted.
When the light comes on red, the assist
to the power steering is lost and handling
operations of the steering wheel become
extremely heavy.
When steering wheel operations are
heavier than usual, grip the steering
wheel firmly and operate it using more
force than usual.
■If the tire pressure warning light
comes on
Be sure to observe the following precau-
tions.
Failure to do so could cause a loss of
vehicle control and result in death or
serious injury.
●Stop your vehicle in a safe place as
soon as possible. Adjust the tire infla-
tion pressure immediately.
●If the tire pressure warning light comes
on even after tire inflation pressure
adjustment, it is prob able that you have
a flat tire. Check the tires. If a tire is flat,
change it with the spare tire and have
the flat tire repaired by the nearest
Lexus dealer.
●Avoid abrupt maneuvering and brak-
ing.
If the vehicle tires deteriorate, you
could lose control of the steering
wheel or the brakes.

4227-2. Steps to take in an emergency
not be charged when the shift lever is in N,
shift the shift lever to P when the vehicle is
stopped.
■If “Traction Battery Needs to be Pro-
tected. Shift into P to Restart.” is dis-
played
This message is displayed when the hybrid
battery (traction battery) charge has
become extremely low because the shift
lever has been left in N for a certain amount
of time.
When operating the vehicle, shift to P and
restart the hybrid system.
■If “Shift Is in N Release Accelerator
Before Shifting ” is displayed
Message is displayed when the accelerator
pedal has been depressed and the shift
lever is in N.
Release the accelerator pedal and shift the
shift lever to D or R.
■If “Depress Brake when Vehicle Is
Stopped Hybrid Syst em May Overheat”
is displayed
Message is displayed when the accelerator
pedal is depressed to maintain the vehicle
position when stopped on a upward slope,
etc.
If this continues, th e hybrid system may
overheat.
Release the accelerator pedal and depress
the brake pedal.
■If “Power Turned Off to Save Battery” is
displayed
This message is disp layed when the power
was cut off due to the automatic power off
function. The next time the hybrid system is
started, increase the engine speed slightly
and maintain it at th at speed for approxi-
mately 5 minutes to recharge the 12-volt
battery.
■If “Headlight System Malfunction Visit
Your Dealer” is displayed
The following systems may be malfunction-
ing. Have the vehicle inspected by your
Lexus dealer immediately.
●The LED headlight system
●AFS (Adaptive Front-li ghting System) (if equipped)
●The automatic headlight leveling system
●Automatic High Beam
■If “Radar Cruise Control Unavailable
See Owner's Manual” is displayed
The dynamic radar cruise control with
full-speed range syst em is suspended tem-
porarily or until the problem shown in the
message is re solved. (causes and coping
methods: P.216)
■If “Radar Cruise Control Unavailable” is
displayed
The dynamic radar cruise control with
full-speed range system cannot be used
temporarily. Use the system when it
becomes available again.
■If a message that indicates the malfunc-
tion of front camera is displayed
The following systems may be suspended
until the problem show n in the message is
resolved. ( P.216, 416)
●PCS (Pre-Collision system)
●LTA (Lane Tracing Assist)
●Automatic High Beam
●RSA (Road Sign Assi st) (if equipped)
●Dynamic radar cruise control with
full-speed range
■If a message that indicates the malfunc-
tion of radar sensor is displayed
The following systems may be suspended
until the problem show n in the message is
resolved. ( P.216, 410)
●PCS (Pre-Collision system)
●LTA (Lane Tracing Assist)
●Dynamic radar cruise control with
full-speed range
■If “Maintenance Required Soon” is dis-
played (U.S.A. only)
Indicates that all maintenance according to
the driven distance on the maintenance
schedule
* should be performed soon.
Comes on approximately 4500 miles
(7200 km) after the message has been
reset. If necessary, perform maintenance.
Please reset the message after the mainte-