
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

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.

5647-2. Steps to take in an emergency
RX450h_U_OM0E013U
■Unlocking the door
Use the mechanical key (P. 133) in order to perform the following opera-
tions:
Insert the mechanical key while
pulling on the driver’s door han-
dle.
Unlocking the door.
Turning the key rearward unlocks the
driver’s door. Turning the key again
unlocks the other doors.
Remove the key, return the handle, and then pull the handle again.
If the electronic key does not operate properly
If communication between the electronic key and vehicle is interrupted
( P. 160) or the electronic key ca nnot be used because the battery is
depleted, the smart access system wi th push-button start and wireless
remote control cannot be used. In such cases, the doors can be opened and
the hybrid system can be started by following the procedure below.
Locking and unlocking the doors
1
2
3

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

6108-2. Customization
RX450h_U_OM0E013U
■Smart access system with push-button start and wireless remote control
( P. 136, 158)
■Smart access system with push-button start ( P. 136, 158)
FunctionDefault settingCustomized setting
Operation buzzer volume5OffOO1 to 7
Operation signal
(Emergency flashers)OnOffOO
Time elapsed before automatic
door lock function is activated if
door is not opened after being
unlocked
60 seconds
Off
—O30 seconds
120 seconds
Open door warning buzzerOffOn—O
Reservation lockOnOff—O
12
FunctionDefault settingCustomized setting
Smart access system with push-
button start On Off O O
The doors that are unlocked
using the smart access system
with push-button start can be
selected Driver’s door All the doors O O
Number of consecutive door
lock operations 2 times As many as desired — O
12

641Alphabetical index
RX450h_U_OM0E013U
Anchor brackets ........................................ 61
AntennaSmart access system with push-button start ................... 158
Anti-lock Brake System (ABS)........ 381 Warning light .......................................537
Approach warning.....................318, 330
Armrest .................................................... 443
Assist grips .............................................. 444
Audio system
*
Automatic air conditioning system .................................................... 405 Air conditioning filter......................... 501
Automatic air conditioning system ................................................. 405
S-FLOW mode ............................... 406
Automatic headlight leveling system .................................................... 253
Automatic High Beam ....................... 255
Automatic light control system.........251
Auxiliary boxes ...........................426, 430
Back door Power back door .................................142
Touchless power back door ......... 144
Wireless remote control ..................142
Back-up lights Replacing light bulbs ......................... 513
Wattage ................................................. 590 Battery (12-volt battery)
Battery checking ................................483
If the 12-volt battery is discharged........................................ 568
Preparing and checking before winter....................................................390
Warning light .......................................536
Battery (traction battery) ..................... 80
Blind Spot Monitor (BSM) ............... 363 Blind Spot Monitor function ............................................367
Rear Cross Traffic Alert function ............................................. 371
Bottle holders .........................................425
Brake Brake Hold ........................................... 249
Fluid ......................................................... 588
Parking brake ...................................... 245
Regenerative braking ......................... 78
Warning light .......................................536
Brake assist ...............................................381
Brake Hold...............................................249 Warning light ....................................... 537
Break-in tips ........................................... 206
Brightness control Instrument panel light control ........ 99
BSM (Blind Spot Monitor) ............... 363 Blind Spot Monitor function......... 367
Rear Cross Traffic Alert function.................................................. 371
B
*: Refer to the “NAVIGATION SYSTEM OWNER’S MANUAL”.

648Alphabetical index
RX450h_U_OM0E013U
Keyless entrySmart access system with push-button start ............................. 158
Wireless remote control ....... 136, 142
Keys..............................................................132 Battery-saving function .................... 160
Electronic key ........................................132
Engine switch ....................................... 232
If the electronic key does not operate properly............................ 564
If you lose your keys ................ 133, 135
Key number plate ................................132
Keyless entry ..........................................132
Mechanical key .................................... 133
Power switch........................................ 232
Replacing the battery ...................... 506
Warning buzzer ...................................137
Wireless remote control ..................132
Knee airbags ............................................. 38 Lane Departure Alert
with steering control (LDA) ......... 302
Lane-Keeping Assist (LKA) .............292
Language (multi-information display) ..................................................... 113
LATCH anchors ........................................ 71
LDA (Lane Departure Alert with steering control) ...................... 302
Lever Auxiliary catch lever ......................... 473
Hood lock release lever................. 473
Shift lever ............................................... 239
Turn signal lever ................................. 244
Wiper lever...............................260, 265
Lexus Climate Concierge................ 404
Lexus Enform
*
Lexus Enform Remote*
LEXUS Enform Safety Connect.................................................452
Lexus parking assist monitor ............347 Display.....................................................348
Precautions ........................................... 354
Lexus Safety System+ .......................... 271 Automatic High Beam.................... 255
Dynamic radar cruise control ..... 323
Dynamic radar cruise control with full-speed range .................... 311
LDA (Lane Departure Alert with steering control) ................. 302
LKA (Lane-Keeping Assist) ........292
PCS (Pre-Collision System) ....... 279
KL