2019 LEXUS RX450H engine overheat

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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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

782Alphabetical index
RX450h_RX450hL_U
Moon roofDoor lock linked moon roof operation ................................... 198
Jam protection function ................... 201
Operation ............................................. 200
MP3 disc.................................................. 433
Multi-information display AWD Control display ...................... 106
Clock...........................................................96
Drive information ................................ 105
Dynamic radar cruise control with full-speed range ................... 306
Energy monitor .....................................124
G-force display.................................... 107
Language .................................................. 113
LKA (Lane-Keeping Assist) ........ 302
Outside temperature ..........................96
PCS (Pre - Collision system) ......287
Settings .....................................................108
Suggestion function ............................. 116
Sway warning display ....................... 106
Warning messages...........................667 Navigation system
*
Noise from under vehicle ........................8
Odometer .................................................. 115
Oil
Engine oil ................................................. 713
Rear differential oil .............................. 716
Opener Fuel filler door...................................... 276
Hood........................................................595
Power back door ................................ 143
Outside rear view mirrors .................. 193 Adjusting and folding ........................193
Blind Spot Monitor (BSM) .............319
Linked mirror function when reversing..................................194
Mirror position memory ................... 181
Outside rear view mirror defoggers.............................................516
Outside temperature display ..............96
Overheating............................................702
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