
4257-2. 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 th e 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 system monitors the air-
bag sensor assembly, fr ont impact sensors,
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.432
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.428

4457-2. Steps to take in an emergency
7
When trouble arises
of the problem:
The 12-volt battery may be dis-
charged. ( P.449)
The 12-volt battery terminal con-
nections may be loose or corroded.
( P.376)
One of the following may be the cause
of the problem:
One or both of the 12-volt battery
terminals may be disconnected.
( P.376)
The 12-volt battery may be dis-
charged. ( P.449)
Contact your Lexus dealer if the problem
cannot be repaired, or if repair procedures
are unknown.
When the hybrid system does not start,
the following steps can be used as an
interim measure to start the hybrid sys-
tem if the power switch is functioning
normally.
Do not use this starting procedure
except in cases of emergency.
1 Turn the power switch to ON mode
and check that the parking brake is
set. ( P.187, 195)
2 Shift the shift lever to P.
3 Turn the power switch to ACCES-
SORY mode. 4
Press and hold the power switch for
about 15 seconds while depressing
the brake pedal firmly.
Even if the hybrid system can be
started using the above steps, the sys-
tem may be malfunctioning. Have the
vehicle inspected by your Lexus dealer.
The interior lights and head-
lights do not turn on, or the horn
does not sound.
Starting the hybrid system in an
emergency

4497-2. Steps to take in an emergency
7
When trouble arises
When the smart access system with
push-button start is deactivated in custom-
ization setting, the powe r switch will turn to
ACCESSORY mode.
3 Firmly depress the brake pedal and
check that is shown on the
multi-information display.
4 Press the power switch shortly and
firmly.
In the event that the hybrid system still
cannot be started, contact your Lexus
dealer.
■Stopping the hybrid system
Shift the shift lever to P, set the parking
brake, and press the power switch as you
normally do when stopping the hybrid sys-
tem.
■Replacing the key battery
As the above procedure is a temporary
measure, it is recomme nded that the elec-
tronic key battery be replaced immediately
when the battery is depleted. ( P.393)
■Alarm (For Canada)
Using the mechanical key to lock the doors
will not set the alarm system.
If a door is unlocked using the mechanical
key when the alarm system is set, the alarm
may be triggered. ( P.75)
■Changing power switch modes
Release the brake pedal and press the
power switch in step 3 above. The hybrid
system does not start and modes will be
changed each time the switch is pressed.
( P.187)
If the 12-volt battery is dis-
charged
The following procedures may be
used to start the hybrid system if the
vehicle’s 12-volt battery is dis-
charged.
You can also call your Lexus dealer
or a qualified repair shop.

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

4527-2. Steps to take in an emergency
ponents when the vehicle is running at a
low speed for an extended period, such
as in heavy traffic.
■When removing the 12-volt battery ter-
minals
When the 12-volt battery terminals are
removed, the information stored in the
ECU is cleared. Before removing the
12-volt battery terminals, contact your
Lexus dealer.
■Charging the 12-volt battery
The electricity stored in the 12-volt battery
will discharge gradually even when the
vehicle is not in use, due to natural dis-
charge and the draining effects of certain
electrical appliances. If the vehicle is left for
a long time, the 12-volt battery may dis-
charge, and the hybrid system may be
unable to start. (The 12-volt battery
recharges automatically while the hybrid
system is operating.)
■When the 12-volt battery is removed or
discharged
●In some cases, it may not be possible to
unlock the doors using the smart access
system with push-button start when the
12-volt battery is discharged. Use the
wireless remote control or the mechani-
cal key to lock or unlock the doors.
●The hybrid system may not start on the
first attempt after the 12-volt battery has
recharged but will start normally after the
second attempt. This is not a malfunction.
●The power switch mode is memorized by
the vehicle. When the 12-volt battery is
reconnected, the system will return to the
mode it was in before the 12-volt battery
was discharged. Before disconnecting
the 12-volt battery, turn the power switch
off.
If you are unsure what mode the power
switch was in before the 12-volt battery
discharged, be especially careful when
reconnecting the 12-volt battery.
●The power back door mu st be initialized.
( P.119)
■When replacing the 12-volt battery
●RX450h: Use a Central Degassing type
12-volt battery (European Regulations). RX450hL: Use a 12-volt battery
designed for this vehicle.
●RX450h: Use a 12-volt battery that the
case size is same
as the previous one
(LN2), 20 hour rate capacity (20HR) is
equivalent (60Ah) or greater, and per-
formance rating (CCA) is equivalent
(460A) or greater.
• If the sizes differ, the 12-volt battery can- not be properly secured.
• If the 20 hour rate capacity is low, even if
the time period where the vehicle is not
used is a short time, the 12-volt battery
may discharge and the hybrid system
may not be able to start.
●Use a 12-volt battery with a handle. If a
12-volt battery without a handle is used,
removal is more difficult.
●After replacing, firm ly attach the follow-
ing items to the exhaust hole of the
12-volt battery.
• Use the exhaust hose that was attached to the 12-volt battery before replacing
and confirm that it is firmly connected to
the hole section of the vehicle.
• Use the exhaust hole plug included with the 12-volt battery re placed or the one
installed on the 12-volt battery prior to
the replacement. (Depending on the
12-volt battery to be replaced, the
exhaust hole may be plugged.)
RX450h
Exhaust hole plug
Exhaust hole
A
B

4818-2. Customization
8
Vehicle specifications
■Gauges, meters and multi-information display (P.78, 83, 88)
Function*1Default settingCustomized setting
LanguageEnglishFrenchOO—Spanish
Units*2miles (MPG)
km (km/L)
OO—km (L/100km)
miles (MPG Impe-
rial)
Drive information 1
Current fuel con-sumption
Customizable items: P.90—O—
Average fuel econ-
omy (after reset)
Drive information 2
Distance (driving range)
Average vehicle
speed (after reset)
Drive information 3
Average fuel econ- omy (after refuel)
Elapsed time (after start)
Clock12-hour display24-hour display—O—
Pop-up displayOnOff—O—
Accent color*3Color 1Color 2OO—
Needle*4Color 1Color 2—O—Color 3
Tachometer settingChange according to driving modeAlways tachometer
—O—Always Hybrid Sys- tem Indicator
Rev indicator*44000 r/min.
2000 - 6000 r/min.
—O—
Off
Rev peak*4OnOff—O—
ABC

4908-2. Customization
■PKSB (Parking Support Brake)* ( P.266)
*:If equipped
■Driving mode select switch ( P.281)
*:If equipped
■Front automatic air conditioning system ( P.304)
*:If equipped
■Seat heaters*/seat ventilators* ( P.318)
*:If equipped
FunctionDefault settingCustomized setting
PKSB (Parking Support Brake)
functionOnOff—O—
FunctionDefault settingCustomized setting
Powertrain control in custom-
ized mode
*NormalPowerO——Eco
Chassis control in customized
mode
*NormalSportO——
Air conditioning operation in
customized mode
*NormalEcoO——
FunctionDefault settingCustomized setting
A/C auto switch operationOnOffO—O
Exhaust gas sensor sensitivity*Standard-3 to 3O—O
FunctionDefault settingCustomized setting
Driver’s seat temperature pref-
erence in automatic modeStandard-2 (cooler) to 2
(warmer)O—O
Front passenger’s seat tem-
perature preference in auto-
matic mode
Standard-2 (cooler) to 2 (warmer)O—O
ABC
ABC
ABC
ABC

513Alphabetical Index
Alphabetical Index
A
A/CAir conditioning filter ...............................390
Front automatic air conditioning system.........................................................................304
Front seat concentr ated airflow mode
(S-FLOW)................................................... 312
Micro dust and pollen filter...................... 311
Rear automatic air conditioning system ...........................................................................315
ABS (Anti-lock Brake System).............. 283 Warning light ............................................... 420
ACA (Active Cornering Assist) ........... 284
Active Cornering Assist (ACA) ........... 284
Adaptive Front-lighting System (AFS)202
Adaptive Variable Suspension System284
AFS (Adaptive Front-lighting System)202
AHB (Automatic High Beam) ............... 203
Air conditioning filter ................................. 390
Air conditioning system Air conditioning filter ...............................390
Front automatic air conditioning system.........................................................................304
Front seat concentr ated airflow mode
(S-FLOW)................................................... 312
Micro dust and pollen filter...................... 311
Rear automatic air conditioning system ...........................................................................315
Airbags Airbag operating conditions................... 33
Airbag precautions for your child ........ 36
Correct driving posture ............................ 25
Curtain shield airbag operating condi- tions .................................................................. 33
Curtain shield airbag precautions ....... 36
Front passenger occupant classification system ............................................................. 39
General airbag precautions ................... 36
Locations of airbags.................................... 30
Modification and disposal of airbags . 38
Side airbag operating conditions ......... 33 Side airbag precautions ............................ 36
Side and curtain shie
ld airbags operating
conditions ...................................................... 33
Side and curtain shield airbags precau- tions .................................................................. 36
SRS airbags......................................................30
SRS warning light.......................................420
Alarm ................................................................... 75 Warning buzzer .......................................... 418
Anchor brackets ..................................... 46, 57
Antennas (smart acc ess system with
push-button start).......................................125
Anti-lock Brake System (ABS).............. 283 Warning light ...............................................420
Approach warning...................................... 244
Armrest............................................................ 342
Assist grips ..................................................... 342
Audio system-linked display ...................... 92
Automatic headlight leveling system ....201
Automatic High Beam .............................. 203
Automatic light control system..............200
Auxiliary boxes ................................... 329, 331
Average fuel economy................................. 90
Average vehicle speed ................................ 90
AWD Control.................................................... 91
B
Back door .......................................................... 113
Back-up light Wattage ......................................................... 468
Back-up lights Replacing light bulbs ...................400, 406
Battery (12-volt battery) Battery checking ........................................ 376
If the 12-volt battery is discharged ....449
Preparing and checking before winter............................................................................291
Warning light ................................................ 419
Battery (traction batter y) ............................ 69
Blind Spot Monitor (BSM)........................247
Bottle holders ................................................ 328