Page 459 of 660

4596-1. Maintenance and care
6
Maintenance and care
RX450h_U_OM0E013U
■Note for a smart access system with push-button start
●If the door handle becomes wet while the electronic key is within the effective range,
the door may lock and unlock repeatedly. Place the key in a position 6 ft. (2 m) or more
separate from the vehicle while the vehicle is being washed. (Take care to ensure that
the key is not stolen.)
●If the electronic key is inside the vehicle and a door handle becomes wet during a car
wash, a buzzer will sound outside the vehicle. To turn off the alarm, lock all the doors.
●Set the electronic key to battery-saving mode to disable the sm art access system with
push-button start. ( P. 159)
■Aluminum wheels
●Remove any dirt immediately by using a neut ral detergent. Do not use hard brushes or
abrasive cleaners. Do not use stro ng or harsh chemical cleaners.
Use the same mild detergent as used on the paint.
●Do not use detergent on the wheels when they are hot, for example after driving for
long distance in the hot weather.
●Wash detergent from the wheels immediately after use.
■Bumpers
Do not scrub with abrasive cleaners.
■Front side windows water-repellent coating
●The following precautions can extend the effectiveness of the water-repellent coating.
• Remove any dirt, etc. from the front side windows regularly.
• Do not allow dirt and dust to accumulate on the windows for a long period. Clean the windows with a soft, damp cloth as soon as possible.
• Do not use wax or glass cleaners that co ntain abrasives when cleaning the windows.
• Do not use any metallic objects to remove condensation build up.
●When the water-repellent performance has become insufficient, the coating can be
repaired. Contact your Lexus dealer.
Page 484 of 660

4846-3. Do-it-yourself maintenance
RX450h_U_OM0E013U
Make sure that the 12-volt battery terminals are not corroded and that there are
no loose connections, cracks, or loose clamps. Terminals
Hold-down clamp
Install the 12-volt battery cover with the
clips. Push up center position
Insert
Press
■Before recharging
When recharging, the 12-volt battery produces hydrogen gas which is flammable and
explosive. Therefore, observe the following precautions before recharging:
●If recharging with the 12-volt battery installed on the vehicle, be sure to disconnect the
ground cable.
●Make sure the power switch on the charge r is off when connecting and disconnecting
the charger cables to the 12-volt battery.
■After recharging/reconnecting the 12-volt battery
●The hybrid system may not start. Follow the procedure below to initialize the system.
Shift the shift lever to P.
Open and close any of the doors.
Restart the hybrid system.
●Unlocking the doors using the smart access system with push-button start may not be
possible immediately after reconnecting the 12-volt battery. If this happens, use the
wireless remote control or the mechan ical key to lock/unlock the doors.
●Start the hybrid system with the power sw itch in ACCESSORY mode. The hybrid sys-
tem may not start with the power switch turned off. However, the hybrid system will
operate normally from the second attempt.
Exterior
1
2
Installing the 12-volt battery cover
1
2
3
1
2
3
Page 506 of 660
5066-3. Do-it-yourself maintenance
RX450h_U_OM0E013U
●Flathead screwdriver
●Lithium battery CR2032
Take out the mechanical key.
Remove the cover.
To prevent damage to the key, cover the
tip of the flathead screwdriver with a
tape.
Remove the depleted battery.
Insert a new battery with the “+” termi-
nal facing up.
Electronic key battery
Replace the battery with a new one if it is depleted.
You will need the following items:
Replacing the battery
1
2
3
Page 507 of 660

5076-3. Do-it-yourself maintenance
6
Maintenance and care
RX450h_U_OM0E013U
■Use a CR2032 lithium battery
●Batteries can be purchased at your Lexus dealer, local electrical appliance shops or
camera stores.
●Replace only with the same or equivalent type recommended by the manufacturer.
●Dispose of used batteries according to the local laws.
■If the electronic key battery is depleted
The following symptoms may occur:
●The smart access system with push-button start and wireless remote control will not
function properly.
●The operational range will be reduced.
WARNING
■Removed battery and other parts
These parts are small and if swallowed by a child, they can cause choking. Keep away
from children. Failure to do so coul d result in death or serious injury.
NOTICE
■For normal operation after replacing the battery
Observe the following precautions to prevent accidents:
●Always work with dry hands.
Moisture may cause the battery to rust.
●Do not touch or move any other co mponent inside the remote control.
●Do not bend either of the battery terminals.
Page 527 of 660

527
7When trouble arises
RX450h_U_OM0E013U
7-1. Essential informationEmergency flashers ..................528
If your vehicle has to be stopped in an
emergency................................. 529
7-2. Steps to take in an emergency
If your vehicle needs to be towed ...........................................530
If you think something is wrong ...........................................535
If a warning light turns on or a warning buzzer
sounds.......................................... 536
If a warning message is displayed..................................... 543
If you have a flat tire .................. 549
If the hybrid sy stem will not
start ................................................ 561
If the shift lever cannot be shifted from P............................ 563
If the electronic key does not operate properly ............. 564
If the 12-volt battery is discharged .................................568
If your vehicle overheats ......... 574
If the vehicle becomes stuck ............................................. 578
Page 544 of 660

5447-2. Steps to take in an emergency
RX450h_U_OM0E013U
*: A buzzer sounds the first time a message is shown on the multi-information display.
●If the following messages are shown, there may be a malfunction.
Immediately stop the vehicle in a safe place and contact your Lexus dealer.
Continuing to drive the vehicle may be dangerous. • “Braking Power Low Stop in a Safe Place See Owner’s Manual”
• “Oil Pressure Low Stop in a Safe Place See Owner’s Manual”
• “Charging System Malfunction See Owner’s Manual”
●If the following messages are shown, there may be a malfunction.
Immediately have the vehicle inspected by your Lexus dealer.• “Hybrid System Malfunction”
•“Check Engine”
• “Hybrid Battery System Malfunction”
• “Accelerator System Malfunction”
• “Access System with Elec. Key Malfunction See Owner’s Manual”
●If “Engine Coolant Temp High Stop in a Safe Place See Owner’s Manual” is
shown, following the instructions, accordingly. ( P. 574)
FlashesSounds
Indicates a situation, such as when
damage to the vehicle or danger may
result
Comes
onDoes not sound
Indicates a condition, such as malfunc-
tion of electrical components, their
condition, or indicates the need for
maintenance
FlashesDoes not sound
Indicates a situation, such as when an
operation has been performed incor-
rectly, or indicates how to perform an
operation correctly
If a message instructing to refer to the Owner’s Manual is displayed
System
warning
lightWarning buzzer*Warning
Page 546 of 660

5467-2. Steps to take in an emergency
RX450h_U_OM0E013U
■If “Shift Is in N Release Accelerator Before Shifting” is shown
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 System May Overheat”
is shown
Message is displayed when the accelerato r pedal is depressed to maintain the
vehicle position when stopped on a upward slope, etc.
If this continues, the 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 displayed when the power was cut off due to the automatic
power off function.
The next time the hybrid system is star ted, increase the engine speed slightly
and maintain it at that speed for approximately 5 minutes to recharge the 12-
volt battery.
■If “A New Key has been Registered Contact Your Dealer for Details” is dis-
played
This message will be displayed each time the driver's door is opened when the
doors are unlocked from the outside fo r approximately one week after a new
electronic key has been registered.
If this message is displayed but you ha ve not had a new electronic key regis-
tered, ask your Lexus dealer to check if an unknown electronic key (other than
those in your possession) has been registered.
■When “Headlight System Malfunction Visit Your Dealer” is displayed
The following systems may be malfunct ioning. Have the vehicle inspected by
your Lexus dealer immediately.
●The LED headlight system
●The automatic headlight leveling system
●Automatic High Beam (if equipped)
●AFS (Adaptive Front-lighting System) (if equipped)
Page 550 of 660
5507-2. Steps to take in an emergency
RX450h_U_OM0E013U
*: Documentation relating to the wheel lock key, such as the registration and I.D. card, is
inside the glove box.
Location of the spare tire, jack and tools
Jack handle
Wheel nut wrench
Spare tire Wheel lock key* (if equipped)
Jack1
2
3
4
5