
651
8When trouble arises
RX450h_RX450hL_U
8-1. Essential informationEmergency flashers .................. 652
If your vehicle has to be stopped in 
an emergency .......................... 653
8-2.  Steps to take in  an emergency
If your vehicle needs  to be towed................................ 654
If you think something is  wrong ........................................... 659
If a warning light turns on  or a warning buzzer 
sounds..........................................660
If a warning message is  displayed..................................... 667
If you have a flat tire .................. 673
If the hybrid  system will 
not start .......................................690
If the electronic key does  not operate properly ............. 692
If the 12-volt battery is  discharged ................................. 695
If your vehicle overheats ......... 702
If the vehicle becomes  stuck ............................................. 706 

652
RX450h_RX450hL_U8-1. Essential information
Press the switch.
All the turn signal lights will flash. To turn
them off, press the switch once again.
■Emergency flashers
If the emergency flashers are used for a long 
time while the hybrid system is not operat-
ing (while the “READY” indicator is not illu minated), the 12-volt battery may discharge.
Emergency flashers
The emergency flashers are used to warn other drivers when the vehicle has
to be stopped on the road due to a breakdown, etc. 

6608-2. Steps to take in an emergency
RX450h_RX450hL_U
If a warning light turns on or a warning buzzer 
sounds
Calmly perform the following actions if any of the warning lights comes on or
flashes. If a light comes on or flashes, but then goes off, this does not necessar-
ily indicate a malfunction in the system. However, if this continues to occur,
have the vehicle inspecte d by your Lexus dealer.
Warning light and warning buzzer list
Warning lightWarning light/Details/Actions
(U.S.A.)
(Canada)
Brake system warning light 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.
Brake system warning light
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.
(If equipped)
Charging system warning light
Indicates a malfunction in the vehicle’s charging system
 Immediately stop the vehicle in a safe place and contact your
Lexus dealer. Continuing to drive the vehicle may be dangerous.
(U.S.A.)
(Canada)
Malfunction indicator lamp Indicates a malfunction in:
• The hybrid system;
• The electronic engine control system; or
• The electronic throttle control system
 Have the vehicle inspected by your Lexus dealer immediately.
SRS warning light
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. 

6618-2. Steps to take in an emergency
8
When trouble arises
RX450h_RX450hL_U
(U.S.A.)
(Canada)
ABS warning light Indicates a malfunction in:
• The ABS; or
• The brake assist system
 Have the vehicle inspected by your Lexus dealer immediately.
(Flashes)
(U.S.A.)
(Flashes)
(Canada)
Parking brake indicator
It is possible that the parking br ake 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 brak e is fully released, the system is
operating normally.
(Flashes)
Brake hold operated indicator Indicates a malfunction in the brake hold system
 Have the vehicle inspected by your Lexus dealer immediately.
Electric power steering system  warning light (warning buzzer)
Indicates a malfunction in the EPS (Electric Power Steering) sys-
tem
 Have the vehicle inspected by your Lexus dealer immediately.
LKA indicator
Indicates a malfunction in the LKA (Lane-Keeping Assist)
 When “Lane Keeping Assist Unavailable” is displayed on the
multi-information display, turn  the LKA system off, drive the
vehicle for a short time, and then turn the LKA system back on.
(  P. 301)
When a message other than above is displayed, follow the
instructions displayed in the message.
Slip indicator 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, TR AC or Trailer Sway Control sys-
tem is operating
Warning lightWarning light/Details/Actions 

6628-2. Steps to take in an emergency
RX450h_RX450hL_U
(Flashes or illuminates)
PCS warning lightIndicates a malfunction in the PCS (Pre-Collision System) or that
the system is temporarily unavailable due to the vehicle being
extremely hot/cold, or dirt around a front sensor, etc. 
( P. 296, 671)
 Follow the instructions displayed on the multi-information dis-
play. ( P. 296, 671)
If the PCS (Pre-Collision System ) or VSC (Vehicle Stability Con-
trol) system is disabled, the PC S warning light will illuminate.
 P. 296
(Flashes)
ICS OFF indicator
When a buzzer sounds:
Indicates a malfunction in the Intelligent Clearance Sonar 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.
 Clear the dirt, etc.
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.
Driver’s and front passenger’s seat belt reminder light (warning
buzzer)
*1
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.
(RX450h)
(RX450hL)Rear passengers’ seat belt reminder light (warning buzzer)*2
Warns the rear passengers to  fasten their seat belts
 Fasten the seat belt.
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. 664)
Warning lightWarning light/Details/Actions 

6638-2. Steps to take in an emergency
8
When trouble arises
RX450h_RX450hL_U
*1: Driver’s and front passenger’s seat belt warning buzzer:The driver’s seat belt warning buzzer sounds to alert the driver that his or her seat belt
is not fastened. Once the power switch is turned to ON mode, the buzzer sounds for
6 seconds. If the vehicle reaches a speed of 12 mph (20 km/h), the buzzer sounds
once. If the seat belt is still unfastened af ter 24 seconds, the buzzer will sound inter-
mittently for 10 seconds. Then,  if the seat belt is still unfastened, the buzzer will sound
in a different tone for 20 more seconds.
The front passenger’s seat belt warning  buzzer sounds to alert the front passenger
that his or her seat belt is not fastened. Th e buzzer sounds once if the vehicle reaches
a speed of 12 mph (20 km/h). If the seat belt  is still unfastened after 24 seconds, the
buzzer will sound intermittently for 10 seconds.  Then, if the seat belt is still unfastened,
the buzzer will sound in a different tone for 20 more seconds.
*2: Rear passengers’ seat belt warning buzzer:
The rear passengers’ seat belt warning bu zzer sounds to alert the rear passengers
that his or her seat belt  is not fastened. The buzzer so unds for 6 seconds after the
vehicle reaches a speed of 20 km/h (12 mph). Then, if the seat belt is still unfastened,
the buzzer will sound in a different tone for 24 more seconds.
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. 667
Warning lightWarning light/Details/Actions 

6648-2. Steps to take in an emergency
RX450h_RX450hL_U
■SRS warning light
This warning light system monitors the airbag sensor assembly, front impact sensors, side
impact sensors (front door), side impact se nsors (rear), driver’s seat position sensor,
driver’s seat belt buckle sw itch, front passenger occupant  classification system (ECU and
sensors), “AIR BAG ON” indicator light, “A IR BAG OFF” indicator light, front passen-
ger’s seat belt buckle switch, driver’s seat belt pretension er, front passenger’s seat belt
pretensioner and force limiter, airbags, in terconnecting wiring and power sources. 
(  P. 36)
■Front passenger detection sensor, seat  belt reminder and warning buzzer
●If luggage is placed on the front passenger  seat, the front passenger detection sensor
may cause the warning light to flash and the warning buzzer to sound even if a passen-
ger is not sittin g in the seat.
●If a cushion is placed on the seat, the sens or may not detect a passenger, and the warn-
ing light may not operate properly.
■Electric power steering system  warning light (warning buzzer)
When the 12-volt battery charge becomes insu fficient or the voltage temporarily drops,
the electric power steering system warning light may come on and the warning buzzer
may sound.
■If the malfunction indicator lamp comes on while driving
First check the following:
●Is the fuel tank empty?
If it is, fill the fu el 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 severa l trips, contact your Lexus dealer as soon as
possible.
■When the tire pressure warning light comes on
Inspect the tires to check if a tire is punctured.
If a tire is punctured:  P. 673
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 comes on
After the temperature of the tires has lowere d sufficiently, check the inflation pressure
of each tire and adjust th em to the specified level.
If the warning light does not turn off even after several minutes have elapsed, check
that the inflation pressure of each tire is  at the specified level and perform initialization.
(  P. 613)
If the warning light does not turn off severa l minutes after the initialization has been per-
formed, have the vehicle inspected by your Lexus dealer immediately.
If the tire pressure wa rning 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 immediately.
1
2 

6658-2. Steps to take in an emergency
8
When trouble arises
RX450h_RX450hL_U
■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 caus ed by temperature. In this case, adjusting
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 warning 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 warnin g light will go off after a few
minutes.
■Conditions that the tire pressure wa rning system may not function properly
 P. 616
■Warning buzzer
In some cases, the buzzer ma y not be heard due to being in a noisy location or audio
sound.
■Customization
Some functions can be customized. ( P. 736)
WARNING
■If both the ABS and the brake sy stem warning lights remain on
Stop your vehicle in a safe place immediat ely and contact your Lexus dealer. The vehi-
cle will become extremely unstable during br aking, and the ABS system may fail, which
could cause an accident resultin g 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 steering 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 precaution s. 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 inflation pressure
immediately. 
●If the tire pressure warning light comes on  even after tire inflation pressure adjust-
ment, it is probable 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 braking. If the vehicle tires deteriorate, you could lose
control of the steering wheel or the brakes.
■If a blowout or sudden air leakage should occur
The tire pressure warning system may not activate immediately.