Page 543 of 660

5437-2. Steps to take in an emergency
7
When trouble arises
RX450h_U_OM0E013U
The warning lights and warning buzzers operate as follows depending on the
content of the message. If a message indicates the need for inspection by a
dealer, have the vehicle inspected by your Lexus dealer immediately.
If a warning message is displayed
The multi-information display shows warn ings of system malfunctions, incor-
rectly performed operations, and messag es that indicate a need for mainte-
nance. When a message is shown, perform the correction procedure
appropriate to the message.
Except F SPORT modelsF SPORT models
Master warning light
The master warning light also comes on or flashes in order to indicate that a message
is currently being displayed on the multi-information display.
Multi-information display
If any of the warning messages are show n again after the following actions have
been performed, contact your Lexus dealer.
Messages and warnings
1
2
System
warning light
Warning buzzer*Warning
Comes on
Sounds Indicates an important situation, such
as when a system related to driving is
malfunctioning or that danger may
result if the correction procedure is not
performed
Comes on
or flashesSounds
Indicates an important situation, such
as when the systems shown on the
multi-information display may be mal-
functioning
Page 548 of 660

5487-2. Steps to take in an emergency
RX450h_U_OM0E013U
■If “Maintenance Required Visit Your Dealer” is displayed (U.S.A. only)
Indicates that all maintenance is required to correspond to the driven distance
on the maintenance schedule
*.
Comes on approximately 5000 miles (8000 km) after the message has
been reset.
(The indicator will not work properly unless the message has been reset.)
Perform the necessary maintenance. Please reset the message after the main-
tenance is performed. ( P. 466)
*: Refer to the separate “Scheduled Maintenance” or “Owner’s Manual Supplement”
for the maintenance interval applicable to your vehicle.
■System warning lights
The master warning light does not come on or flash in the following cases. Instead, a sep-
arate system warning light will come on along with a message shown on the multi-infor-
mation display.
●“Braking Power Low Visit Your Dealer”:
The brake system warning light (yellow) come on. ( P. 536)
●“Antilock Brake System Malfunction Visit Your Dealer”:
The ABS warning light comes on. ( P. 537)
●“Charging System Malfunction See Ow ner's Manual” (F SPORT models):
The charging system warning light comes on. ( P. 536)
■Warning buzzer
P. 540
NOTICE
■“High Power Consumption Partial Limit On AC/Heater Operation” is frequently
shown
There is a possible malfunction relating to the charging system or the 12-volt battery
may be deteriorating. Have the vehicle inspected by your Lexus dealer.
Page 561 of 660

5617-2. Steps to take in an emergency
7
When trouble arises
RX450h_U_OM0E013U
One of the following may be the cause of the problem:
●The electronic key may not be functioning properly. ( P. 564)
●There may not be sufficient fuel in the vehicle’s tank.
Refuel the vehicle.
●There may be a malfunction in the immobilizer system. ( P. 85)
●There may be a malfunction in the steering lock system.
●The hybrid system may be malfunctioni ng due to an electrical problem such
as electronic key battery depletion or a blown fuse. However, depending on
the type of malfunction, an interim meas ure is available to start the hybrid sys-
tem. ( P. 562)
One of the following may be the cause of the problem:
●The 12-volt battery may be discharged. ( P. 568)
●The 12-volt battery terminal connections may be loose or corroded.
( P. 483)
If the hybrid system will not start
Reasons for the hybrid system not star ting vary depending on the situation.
Check the following and perform the appropriate procedure:
The hybrid system will not start even though the correct starting proce-
dure is being followed. ( P. 232)
The interior lights and headlights are d im, or the horn does not sound or
sounds at a low volume.
Page 562 of 660

5627-2. Steps to take in an emergency
RX450h_U_OM0E013U
One of the following may be the cause of the problem:
●The 12-volt battery may be discharged. (P. 568)
●One or both of the 12-volt battery terminals may be disconnected. ( P. 483)
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 system if the power switch is functioning nor-
mally.
Do not use this starting procedur e except in cases of emergency.
Turn the power switch to ON mode an d check that the parking brake is set.
( P. 233, 245)
Shift the shift lever to P.
Turn the power switch to ACCESSORY mode.
Press and hold the power switch for ab out 15 seconds while depressing the
brake pedal firmly.
Even if the hybrid system can be starte d using the above steps, the system may
be malfunctioning. Have the vehicle inspected by your Lexus dealer.
The interior lights and headlights do not turn on, or the horn does not
sound.
Emergency start function
1
2
3
4
Page 570 of 660

5707-2. Steps to take in an emergency
RX450h_U_OM0E013U
Start the engine of the second vehicle. Increase the engine speed slightly and
maintain at that level for approximatel y 5 minutes to recharge the 12-volt bat-
tery of your vehicle.
Open and close any of the doors of your vehicle with the power switch off.
Maintain the engine speed of the seco nd vehicle and start the hybrid system
of your vehicle by turning th e power switch to ON mode.
Make sure the “READY” indicator comes on. If the indicator light does not
come on, contact your Lexus dealer.
Once the hybrid system has started, remove the jumper cables in the exact
reverse order from which they were connected.
Close the exclusive jump starting termin al cover, and reinstall the fuse box
cover to its original position.
Once the hybrid system starts, have th e 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 system while the hybrid system is off.
●Turn off any unnecessary electrical components when the vehicle is running at a low
speed for an extended period , such as in heavy traffic.
■Charging the 12-volt battery
The electricity stored in the 12-volt battery w ill discharge gradually even when the vehicle
is not in use, due to natural discharge and the draining effects of certain electrical appli-
ances. If the vehicle is left for a long time, the 12-volt battery may discharge, 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 un lock 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 mechanical 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 retu rn to the mode it was in before the 12-volt battery was
discharged. Before disconnect ing 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 dis-
charged, be especially careful when reconnecting the 12-volt battery.
●The power back door must be initialized. ( P. 150)
6
7
8
9
10
11
Page 587 of 660

5878-1. Specifications
8
Vehicle specifications
RX450h_U_OM0E013U
*: The coolant capacity is a reference quantity. If replacement is necessary, contact your Lexus dealer.
Cooling system
Capacity*
Gasoline engine
10.7 qt. (10.1 L, 8.9 Imp. qt.)
Power control unit
2.0 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 organic
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.
Electrical system
12-volt battery
Open voltage at 68F (20 C):
12.6 V or higher: Fully charged
12.2 — 12.4 V: Half charged
12.0 V or lower: Discharged
(Voltage is checked 20 minutes after the hybrid
system and all lights are turned off.)
Charging rates5 A max.
Page 590 of 660
5908-1. Specifications
RX450h_U_OM0E013U
Light bulbs
Light bulbsBulb No.WType
Exterior
Front side marker lights*15B
Front turn signal lights*17444NA28/8A
Rear turn signal lights*121A
Back-up lights92116B
Interior
Door courtesy lights*25B
Vanity lights8B
Luggage compartment light5B
A: Wedge base bulbs (amber) B: Wedge base bulbs (clear)
*1: Vehicles with single-beam headlights
*2: Vehicles without door trim ornament lights
Page 614 of 660
6148-2. Customization
RX450h_U_OM0E013U
■Turn signal lever ( P. 244)
■Automatic light control system ( P. 251)
■Lights (P. 251)
*1:Except for Canada
*2: If equipped
■Rain-sensing windshield wipers (P. 260)
FunctionDefault settingCustomized setting
The number of times the turn sig-
nal lights flash automatically
when the turn signal lever is
moved to the first position during
a lane change
3
5
—O7
Off
12
FunctionDefault settingCustomized setting
Light sensor sensitivityStandard-2 to 2OO
Time elapsed before headlights
automatically turn off after doors
are closed 30 seconds
Off
OO
60 seconds
90 seconds
12
FunctionDefault settingCustomized setting
Daytime running lightsOnOff*1OO
Welcome lightingOnOff—O
AFS (Adaptive Front-lighting
System)
*2OnOff—O
12
FunctionDefault settingCustomized setting
Wiper operation when the wiper
switch is in the “AUTO” positionRain-sensing oper-ation
Intermittent opera-
tion linked to vehi- cle speed (with
interval adjuster)
—O
12