Page 693 of 792

6938-2. Steps to take in an emergency
8
When trouble arises
RX450h_RX450hL_U
■Locking the doorWith the door open, push down
the inside lock button.
Close the door.
■Key linked functions
Ensure that the shift lever is in P and depress the brake pedal.
Touch the Lexus emblem side of the
electronic key to the power switch.
When the electronic key is detected, a
buzzer sounds and the power switch will
turn to ON mode.
When the smart access system with
push-button start is deactivated in cus-
tomization setting, the power switch will
turn to ACCESSORY mode.
Firmly depress the brake pedal and check that is shown on the multi-
information display.
Press the power switch shortly and firmly.
In the event that the hybrid system still cannot be operated, contact your Lexus
dealer.
1
Closes the windows and the moon roof* or
panoramic moon roof* (turn and hold)
Opens the windows and the moon roof
* or
panoramic moon roof
* (turn and hold)
These settings must be customized at your
Lexus dealer.
*: If equipped
Starting the hybrid system
2
1
2
1
2
3
4
Page 694 of 792

6948-2. Steps to take in an emergency
RX450h_RX450hL_U
■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 system.
■Replacing the key battery
As the above procedure is a temporary measure, it is recommended that the electronic
key battery be replaced immediately when the battery is depleted. (P. 630)
■Changing power switch modes
Release the brake pedal and press the power switch in step above.
The hybrid system does not start and modes will be changed each time the switch is
pressed. ( P. 240)
■When the electronic key does not work properly
●Make sure that the smart access system wi th push-button start has not been deacti-
vated in the customization setting. If it is off, turn the function on.
(Customizable features P. 740)
●Check if battery-saving mode is set. If it is set, cancel the function. (P. 160)
WARNING
■When using the mechanical key and operating the power windows or the moon roof
or panoramic moon roof
Operate the power window or the moon roof or panoramic moon roof after checking
to make sure that there is no possibility of any passenger having any of their body parts
caught in the window or the moon roof or panoramic moon roof.
Also, do not allow children to op erate the mechanical key. It is possible for children and
other passengers to get caught in the powe r window or the moon roof or panoramic
moon roof.
3
Page 703 of 792

7038-2. Steps to take in an emergency
8
When trouble arises
RX450h_RX450hL_U
Add coolant if necessary.
Water can be used in an emergency
if coolant is unavailable.
Start the hybrid system and turn the air conditioning system on to check
that the radiator cooling fans operate and to check for coolant leaks from
the radiator or hoses.
The fans operate when the air conditioning system is turned on immediately after a
cold start. Confirm that the fans are operating by checking the fan sound and air
flow. If it is difficult to check these, tu rn the air conditioning system on and off
repeatedly. (The fans may not operate in freezing temperatures.)
If the fans are not operating:
Stop the hybrid system immediately and contact your Lexus dealer.
If the fans are operating:
Have the vehicle inspected at the nearest Lexus dealer.
Check if “Engine Coolant Temp High Stop in a Safe Place See Owner’s
Manual” is shown on the multi-information display.
If the message does not disappear:
Stop the hybrid system and contact your Lexus dealer.
If the message is not displayed:
Have the vehicle inspected at the nearest Lexus dealer.
5
6
7
8
Page 705 of 792

7058-2. Steps to take in an emergency
8
When trouble arises
RX450h_RX450hL_U
Start the hybrid system and check if “Hybrid System Overheated Reduced
Output Power” is shown on the multi-information display.
If the message does not disappear:
Stop the hybrid system and contact your Lexus dealer.
If the message is not displayed:
Have the vehicle inspected at the nearest Lexus dealer.
WARNING
■To prevent an accident or injury when inspecting under the hood of your vehicle
Observe the following precautions.
Failure to do so may result in serious injury such as burns.
●If steam is seen coming from under the h ood, do not open the hood until the steam
has subsided. The engine compartment may be very hot.
●After the hybrid system has been turned off, check that the “READY” indicator is off.
When the hybrid system is operating, the gasoline engine may automatically start, or
the cooling fans may suddenly operate even if the gasoline engine stops. Do not
touch or approach rotating parts such as th e fans, which may lead to fingers or cloth-
ing (especially a tie, a scarf or a muffler) getting caught, resulting in serious injury.
●Do not loosen the radiator cap and the coolant reservoir caps wh ile the hybrid system
and radiator are hot.
High temperature steam or coolant could spray out.
NOTICE
■When adding engine/power control unit coolant
Add coolant slowly after the hybrid system has cooled down sufficiently. Adding cool
coolant to a hot hybrid system too quickly can cause damage to the hybrid system.
■To prevent damage to the cooling system
Observe the following precautions:
●Avoid contaminating the coolant with foreig n matter (such as sand or dust etc.).
●Do not use any coolant additive.
6
Page 713 of 792
7139-1. Specifications
9
Vehicle specifications
RX450h_RX450hL_U
*: The engine oil capacity is a reference quantity to be used when changing the engineoil. Warm up the engine and turn off the hybrid system, wait more than 5 minutes, and
check the oil level on the dipstick.
Hybrid battery (traction battery)
TypeNickel-Metal hydride battery
Voltage9.6 V/module
Capacity6.5 Ah (3HR)
Quantity30 modules
Overall voltage288 V
Lubrication system
Oil capacity
(Drain and refill — reference
*)
With filterVehicles with towing package
5.8 qt. (5.5 L, 4.8 Imp. qt.)
Vehicles without towing package
5.7 qt. (5.4 L, 4.8 Imp. qt.)
Without filter5.6 qt. (5.3 L, 4.7 Imp. qt.)
Page 715 of 792

7159-1. Specifications
9
Vehicle specifications
RX450h_RX450hL_U
*: The coolant capacity is a reference quantity. If replacement is necessary, contact your Lexus dealer.
Cooling system
Capacity*
Gasoline
engine
RX450h
10.7 qt. (10.1 L, 8.9 Imp. qt.)
RX450hL
13.2 qt. (12.5 L, 11 Imp. qt.)
Power control
unit2.0 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-basednon-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 (20C):
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 766 of 792

766
RX450h_RX450hL_UWhat to do if... (Troubleshooting)
What to do if... (Troubleshooting)
●If you lose your mechanical keys, ne
w genuine mechanical keys can be made
by your Lexus dealer. ( P. 133)
●If you lose your electronic keys, the risk of vehicle theft increases significantly.
Contact your Lexus dealer immediately. ( P. 135)
●Is the electronic key battery weak or depleted? ( P. 630)
●Is the power switch in ON mode?
When locking the doors, turn the power switch off. (P. 240)
●Is the electronic key left inside the vehicle?
When locking the doors, make sure that you have the electronic key on your
person.
●The function may not operate properly du e to the condition of the radio wave.
( P. 160)
●Is the child-protector lock set?
The rear door cannot be opened from in side the vehicle when the lock is set.
Open the rear door from outside and then unlock the child-protector lock.
( P. 139)
If you have a problem, check the foll owing before contacting your Lexus
dealer.
The doors cannot be locked, unlocked, opened or closed
You lose your keys
The doors cannot be locked or unlocked
The rear door cannot be opened
Page 768 of 792

768What to do if... (Troubleshooting)
RX450h_RX450hL_U
●The seat belt reminder light is flashing
Are the driver and the passengers wearing the seat belts?
( P. 662, 662)
●The parking brake indicator is on
Is the parking brake released? ( P. 253)
Depending on the situation, other types of warning buzzer may also sound.
( P. 660, 667)
●Did anyone inside the vehicle open a door during setting the alarm?
The sensor detects it and the alarm sounds. ( P. 86)
Do one of the following to stop the alarms:
• Unlock the doors.
• Turn the power switch to ACCESSORY or ON mode, or start the hybrid system.
●Is the message displayed on the multi-information display?
Check the message on the multi-information display. ( P. 667)
●When a warning light turns on or a warning message is displayed, refer to
P. 660, 667.A warning buzzer sounds during driving
An alarm is activated and the horn sounds
A warning buzzer sounds when leaving the vehicle
A warning light turns on or a warning message is displayed