
5917-2. Maintenance
7
Maintenance and care
RX450h_RX450hL_U
Vehicle exterior
ItemsCheck points
Doors• Do the doors operate smoothly?
Engine hood• Does the engine hood lock system work properly?
Fluid leaks• There should not be any signs of fluid leakage after
the vehicle has been parked.
Tires
• Is the tire inflation pressure correct?
• The tires should not be damaged or excessively worn.
• Have the tires been rotated according to the mainte- nance schedule?
• The wheel nuts should not be loose.
Windshield wipers/
rear window wiper
•The wiper blades should no t show any signs of crack-
ing, splitting, wear, contamination or deformation.
• The wiper blades should clear the windshield/rear
window without streaking or skipping.
WARNING
■If the hybrid system is operating
Turn the hybrid system off and ensure that there is adequate ventilation before per-
forming maintenance checks.

5957-3. Do-it-yourself maintenance
7
Maintenance and care
RX450h_RX450hL_U
Pull the hood lock release lever.
The hood will pop up slightly.
Pull up the auxiliary catch lever and
lift the hood.
Hood
Release the lock from the inside of the vehicle to open the hood.
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WARNING
■Pre-driving check
Check that the hood is fully closed and locked.
If the hood is not locked properly, it may op en while the vehicle is in motion and cause
an accident, which may result in death or serious injury.

6958-2. Steps to take in an emergency
8
When trouble arises
RX450h_RX450hL_U
If you have a set of jumper (or booster) cables and a second vehicle with a 12-volt
battery, you can jump start your vehicle by following the steps below.
Confirm that the electronic key is
being carried.
When connecting the jumper (or
booster) cables, depe nding on the situa-
tion, the alarm may activate and doors
locked. (
P. 87)
Open the hood ( P. 595) and fuse
box cover.
Open the exclusive jump starting
terminal cover.
If the 12-volt battery is discharged
The following procedures may be used to start the hybrid system if the vehi-
cle’s 12-volt battery is discharged.
You can also call your Lexus deal er or a qualified repair shop.
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7028-2. Steps to take in an emergency
RX450h_RX450hL_U
■“Engine Coolant Temp High Stop in a Safe Place See Owner’s Manual” is
shown on the multi-information displayStop the vehicle in a safe place and turn off the air conditioning system, and
then stop the hybrid system.
If you see steam:
Carefully lift the hood after the steam subsides.
If you do not see steam:
Carefully lift the hood.
After the hybrid system has
cooled down sufficiently, inspect
the hoses and radiator core (radi-
ator) for any leaks.Radiator
Cooling fans
If a large amount of coolant leaks,
immediately contact your Lexus
dealer.
The coolant level is satisfactory if
it is between the “FULL” and
“LOW” lines on the reservoir.Reservoir
“FULL” line
“LOW” line
Radiator cap
If your vehicle overheats
The following may indicate that your vehicle is overheating.
●The needle of the engine coolant temperature gauge ( P. 96) enters the
red zone, or a loss of hybrid system power is experienced. (For example, the
vehicle speed does not increase.)
●“Engine Coolant Temp High Stop in a Safe Place See Owner’s Manual” or
“Hybrid System Overheated Reduced Output Power” is shown on the
multi-information display.
●Steam comes out from under the hood.
Correction procedures
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7048-2. Steps to take in an emergency
RX450h_RX450hL_U
■If “Hybrid System Overheated Reduced Output Power” is shown on the
multi-information displayStop the vehicle in a safe place.
Stop the hybrid system an d carefully lift the hood.
After the hybrid system has
cooled down, inspect the hoses
and radiator core (radiator) for
any leaks. Radiator
Cooling fans
If a large amount of coolant leaks,
immediately contact your Lexus
dealer.
The coolant level is satisfactory if
it is between the “FULL” and
“LOW” lines on the reservoir.Reservoir
“FULL” line
“LOW” line
Add coolant if necessary.
Water can be used in an emergency
if coolant is unavailable.
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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.
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776Alphabetical index
RX450h_RX450hL_U
Emergency, in case ofIf a warning buzzer sounds.......... 660
If a warning light turns on.............. 660
If a warning message is displayed.............................................667
If the 12-volt battery is discharged ........................................ 695
If the electronic key does not operate properly.............................692
If the hybrid system will not start ............................................... 690
If you have a flat tire ..........................673
If you lose your keys ................ 133, 135
If you think something is wrong .................................................. 659
If your vehicle becomes stuck ..................................................... 706
If your vehicle has to be stopped in an
emergency........................................ 653
If your vehicle needs to be towed................................................... 654
If your vehicle overheats ................702
Energy monitor ....................................... 124 Engine
ACCESSORY mode ..................... 240
Compartment ..................................... 597
Engine switch ...................................... 239
Hood........................................................595
How to start the hybrid system .................................................. 239
Identification number......................... 712
If your vehicle has to be stopped in an emergency..........653
Ignition switch (power switch) .... 239
Overheating......................................... 702
Power switch ....................................... 239
Engine coolant Capacity................................................... 715
Checking ................................................ 601
Preparing and checking before winter ....................................390
Engine coolant temperature gauge .........................................................96
Engine oil Capacity................................................... 713
Checking .............................................. 598
Preparing and checking before winter ....................................390
Engine oil maintenance data ........... 600
Engine switch ......................................... 239
Enhanced VSC ..................................... 382
EPS (Electronic Power Steering) ........ 383 Warning light .........................................661
EV drive mode .......................................244
EV indicator ............................................... 76
Event data recorder (EDR).....................11

778Alphabetical index
RX450h_RX450hL_U
Hands-free system (for cellular phone) .............................461
Head restraints ....................................... 186
Head-up display....................................... 118
Headlight cleaner................................. 267
Headlights ............................................... 258 Automatic headlight leveling ...... 260
Automatic High Beam .................... 262
Light switch .......................................... 258
Replacing light bulbs ........................637
Wattage ....................................................719
Windshield wiper linked headlight illumination..................... 261
Heated steering wheel ....................... 526
Heaters Automatic air conditioning system ..................................... 507, 522
Heated steering wheel ....................526
Outside rear view mirrors .............. 516
Seat heaters ..............................526, 527
High mounted stoplight Replacing ...............................................637
Hill-start assist control ........................ 382
Hood .......................................................... 595 Open ....................................................... 595
Hooks Cargo hooks ....................................... 540
Cargo net hooks ............................... 540
Front passenger footwell hooks ....................................................557
Grocery bag hooks........................... 541
Retaining hooks (floor mat) ............. 28 Horn.............................................................189
HUD (Head-up display)....................... 118
Humidity sensor...................................... 521
Hybrid battery air vent ........................... 79
Hybrid battery (traction battery)
Location .................................................... 78
Specification ........................................... 713
Hybrid system............................................ 74 Emergency shut off system ..............79
Energy monitor/consumption screen....................... 124
EV drive mode ................................... 244
High voltage components ............... 78
Hybrid System Indicator ................... 99
Hybrid system precautions ............. 78
Hybrid vehicle driving tips ........... 388
If the hybrid system will not start....................................................... 690
Overheating......................................... 702
Power (ignition) switch................... 239
Regenerative braking ..........................76
Starting the hybrid system............. 239
Vehicle proximity notification system ..................................................... 75
Hybrid System Indicator .......................99
Hybrid transmission .............................246 If the shift lever cannot be shifted from P ...................................250
Paddle shift switches............ 247, 248
S mode.................................................... 248
H