engine overheat LEXUS RC300H 2017 Owners Manual

TABLE OF CONTENTS6
RC300h_EE(OM24740E)
7-1. Maintenance and care
Cleaning and protecting
the vehicle exterior.................460
Cleaning and protecting
the vehicle interior ..................464
7-2. Maintenance
Maintenance
requirements............................. 467
7-3. Do-it-yourself
maintenance
Do-it-yourself service
precautions ................................469
Hood ................................................ 471
Positioning a floor jack............. 472
Engine compartment................ 473
12-volt battery............................... 481
Tires .................................................484
Replacing the tire .......................499
Tire inflation pressure.............. 505
Wheels............................................507
Air conditioning filter............... 509
Electronic key battery .................511
Checking and replacing
fuses ............................................... 514
Light bulbs ...................................... 518
8-1. Essential information
Emergency flashers ................. 528
If your vehicle has
to be stopped
in an emergency ......................529
8-2. Steps to take
in an emergency
If your vehicle needs
to be towed............................... 530
If you think something
is wrong .......................................536
If a warning light turns
on or a warning buzzer
sounds.......................................... 537
If a warning message
is displayed.................................542
If you have a flat tire...................563
If the hybrid system will
not start........................................ 576
If the electronic key does
not operate properly .............578
If the 12-volt battery
is discharged ............................ 582
If your vehicle overheats .........587
If the vehicle becomes
stuck..............................................592
7Maintenance and care8When trouble arises

15Pictorial index
RC300h_EE(OM24740E)
Windshield wipers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 241
Precautions against winter season . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 337
To prevent freezing (windshield wiper de-icer)*1 . . . . . . . . . . . . . . . . . . . . . . P. 439 Precautions against car wash . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 462
Fuel filler door . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P . 249
Refueling method. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 249 Fuel type/fuel tank capacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 598
Tires. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .P. 484
Tire size/inflation pressure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 604 Winter tires/tire chain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 33 7
Checking/rotation/tire pressure warning system . . . . . . . . . . . . . . . . . . . . . . P. 484 Coping with flat tires. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 563
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .P. 471
Opening . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 471 Engine oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 599 Coping with overheating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 587
Warning messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 544
Headlights/front position lights/daytime running lights/
turn signal lights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .P. 229, 232
Front fog lights*1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .P. 239
Rear fog light*3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 239
Back up light*2
Shifting the shift lever to R . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 222
Tail lights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .P. 232
Stop lights
Emergency brake signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 305
License plate lights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .P. 232
Rear fog light*2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 239
Back up light*3
Shifting the shift lever to R . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 222
4
5
6
7
Light bulbs of the exterior lights for driving
(Replacing method: P. 518, Watts: P. 605)
*1: If equipped
*2: Left-hand drive vehicles
*3: Right-hand drive vehicles
8
9
10
11
12
13

1202. Instrument cluster
RC300h_EE(OM24740E)
■Pop-up display
●In some situations, such as when a switch operation is performed, a pop-up display will be temporarily displayed on the multi-information display or the odometer/trip meter
screen (F SPORT models only).
●Some pop-up displays can be set on/off. ( P. 126)
■Liquid crystal display
Small spots or light spots may appear on th e display. This phenomenon is characteristic of liquid crystal displays, and there is no problem continuing to use the display.
■Customization
The meter display can be customized on the multi-information display. (P. 121)
NOTICE
■To prevent damage to the engine and its components
●Do not let the indicator of the tachometer enter the red zone, as it represents the engine speed range which exceeds the maximum safe engine speed.
●If the engine coolant temperature gauge is in the red zone (H), the engine may beoverheating. In this case, immediately stop the vehicle in a safe place, and check theengine after it has cooled completely. ( P. 587)

2084-1. Before driving
RC300h_EE(OM24740E)
WARNING
Observe the following precautions. Failure to do so may result in death or serious injury.
■When starting the vehicle
Always keep your foot on the brake pedal while stopped with the “READY” indicator is illuminated. This prevents the vehicle from creeping.
■When driving the vehicle
●Do not drive if you are unfamiliar with the location of the brake and accelerator ped-als to avoid depressing the wrong pedal.
• Accidentally depressing the accelerator pedal instead of the brake pedal will
result in sudden acceleration that may lead to an accident. • When backing up, you may twist your body around, leading to a difficulty in oper- ating the pedals. Make sure to operate the pedals properly.
• Make sure to keep a correct driving posture even when moving the vehicle only slightly. This allows you to depress the brake and accelerator pedals properly.• Depress the brake pedal using your right foot. Depressing the brake pedal using
your left foot may delay response in an emergency, resulting in an accident.
●The driver should pay extra attention to pedestrians when the vehicle is powered only
by the electric motor (traction motor). As there is no engine noise, the pedestrians may misjudge the vehicle’s movement.
●Do not drive the vehicle over or stop the vehicle near flammable materials.
The exhaust system and exhaust gases can be extremely hot. These hot parts may cause a fire if there is any flammable material nearby.
●During normal driving, do not turn off the hybrid system. Turning the hybrid system off
while driving will not cause loss of steering or braking control, however, power assist to the steering will be lost. This will make it more difficult to steer smoothly, so you should pull over and stop the vehicle as soon as it is safe to do so.
In the event of an emergency, such as if it becomes impossible to stop the vehicle in the normal way: P. 529
●Use engine braking (downshift) to maintain a safe speed when driving down a steep
hill. Using the brakes continuously may cause th e brakes to overheat and lose effective- ness. ( P. 222)
●Do not adjust the positions of the steering wheel, the seat, or the inside or outside rear view mirrors while driving.Doing so may result in a loss of vehicle control.
●Always check that all passengers’ arms, heads or other parts of their body are notoutside the vehicle.

2104-1. Before driving
RC300h_EE(OM24740E)
WARNING
Observe the following precautions. Failure to do so may result in death or serious injury.
■When the vehicle is stopped
●Do not depress the accelerator pedal unnecessarily.If the shift lever is in any position other than P or N, the vehicle may accelerate sud-denly and unexpectedly, causing an accident.
●In order to prevent accidents due to the vehicle rolling away, always keep depressingthe brake pedal while stopped with the “READY” indicator is illuminated, and applythe parking brake as necessary.
●If the vehicle is stopped on an incline, in order to prevent accidents caused by thevehicle rolling forward or backward, alwa ys depress the brake pedal and securely apply the parking brake as needed.
●Avoid revving or racing the engine. Running the engine at high speed while the vehicle is stopped may cause the exhaustsystem to overheat, which could result in a fire if combustible material is nearby.
■When the vehicle is parked
●Do not leave glasses, cigarette lighters, spray cans, or soft drink cans in the vehicle when it is in the sun.
Doing so may result in the following:
• Gas may leak from a cigarette lighter or spray can, and may lead to a fire. • The temperature inside the vehicle may cau se the plastic lenses and plastic mate-
rial of glasses to deform or crack. • Soft drink cans may fracture, causing the contents to spray over the interior of thevehicle, and may also cause a short circuit in the vehicle’s electrical components.
●Do not leave cigarette lighters in the vehicle. If a cigarette lighter is in a place such as the glove box or on the floor, it may be lit accidentally when luggage is loaded or the
seat is adjusted, causing a fire.
●Do not attach adhesive discs to the windshield or windows. Do not place containers such as air fresheners on the instrument panel or dashboard. Adhesive discs or con-
tainers may act as lenses, causing a fire in the vehicle.
●Do not leave a door or window open if the curved glass is coated with a metallized film such as a silver-colored one. Reflected sunlight may cause the glass to act as a
lens, causing a fire.
●Always apply the parking brake, shift the shift lever to P, stop the hybrid system and lock the vehicle.
Do not leave the vehicle unattended while the “READY” indicator is illuminated. If the vehicle is parked with the shift lever in P but the parking brake is not set, thevehicle may start to move, possibly leading to an accident.
●Do not touch the exhaust pipes while the “READY” indicator is illuminated or imme-diately after turning the hybrid system off.Doing so may cause burns.

3084-5. Using the driving support systems
RC300h_EE(OM24740E)
■Sounds and vibrations caused by the ABS, brake assist, TRC, VSC and hill-start assist control systems
Any of the following conditions may occur when the above systems are operating. None
of these indicates that a malfunction has occurred.
●Vibrations may be felt through the vehicle body and steering.
●A motor sound may be heard after the vehicle comes to a stop.
■ECB operating sound
ECB operating sound may be heard in the follow ing cases, but it does not indicate that a malfunction has occurred.
●Operating sound heard from the engine compartment when the brake pedal is oper-ated.
●Motor sound of the brake system heard from the front part of the vehicle when the
driver’s door is opened.
●Operating sound heard from the engine compartment when one or two minutes passed after the stop of the hybrid system.
■EPS operation sound
When the steering wheel is operated, a motor sound may be heard. This does not indi- cate a malfunction.
■Reactivation of the TRC/VSC systems
Even after the TRC/VSC systems have been turned off, turning the hybrid system off and then on again will automatically reactivate the TRC/VSC systems.
■Reactivation of the TRC system linked to vehicle speed
When only the TRC system is turned off, th e TRC system will turn on when vehicle speed increases. However, when both TRC and VSC systems are turned off, the systems will
not turn on even when vehicle speed increases.
■Reduced effectiveness of the EPS system
The effectiveness of the EPS system is redu ced to prevent the system from overheating when there is frequent steering input over an extended period of time. The steeringwheel may feel heavy as a result. Should this occur, refrain from excessive steering input
or stop the vehicle and turn the hybrid system off. The EPS system should return to nor- mal within 10 minutes.
■Operating conditions of hill-start assist control
When the following four conditions are met, the hill-start assist control will operate:
●The shift lever is in a position other than P or N (when starting off forward/backward on an upward incline).
●The vehicle is stopped.
●The accelerator pedal is not depressed.
●The parking brake is not engaged.
■Automatic system cancelation of hill-start assist control
The hill-start assist control will turn off in any of the following situations:
●The shift lever is moved to P or N.
●The accelerator pedal is depressed.
●The parking brake is engaged.
●Approximately 2 seconds elapse after the brake pedal is released.

5518-2. Steps to take in an emergency
8
When trouble arises
RC300h_EE(OM24740E)
Indicates that the windows are not fully closed (with the
power switch off, and the driver’s door open) A buzzer also sounds. Close all the windows.
(If equipped)
Indicates that the windows and the moon roof are not fully closed (with the power switch off, and the driver’s
door open) A buzzer also sounds. Close all the windows and the moon roof.
Indicates a malfunction in the brake override system
A buzzer also sounds.  Have the vehicle inspected by any authorized Lexus dealer or repairer, or another duly qualified and
equipped professional.
Indicates that engine oil level is low This message may appear if the vehicle is stopped on a
slope. Move the vehicle to a level surface and check to see if the message disappears.A buzzer also sounds.
 Check the level of engine oil, and add if necessary.
Indicates that the hybrid system has overheated This message may be displayed when driving undersevere operating conditions. (For example, when driv-
ing up a long steep hill.) A buzzer also sounds.
 Stop and check. (P. 587)
Warning messageDetails/Actions
(Flashes)
(Flashes)

5878-2. Steps to take in an emergency
8
When trouble arises
RC300h_EE(OM24740E)
●The hybrid system coolant temperature gauge (P. 115) is in the red zone or
a loss of hybrid system power is experi enced. (For example, the vehicle speed
does not increase.)
●“Engine Coolant High Temperature” or “Hybrid System Overheat Output
Power is limited” is shown on the multi-information display.
●Steam comes out from under the hood.
■If the needle of the engine coolant temperature gauge enters the red zone
or “Engine Coolant High Temperature” is shown on the multi-information
display
Stop 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 any autho- rized Lexus dealer or repairer, oranother duly qualified and
equipped professional.
If your vehicle overheats
The following may indicate that your vehicle is overheating.
Correction procedures
1
2
3
1
2

626Alphabetical index
RC300h_EE(OM24740E)
Seat heater precautions ................. 444
Trunk precautions ............................. 153
Cleaning ....................................... 460, 464
Aluminum wheels ................................461
Exterior................................................... 460
Interior ..................................................... 464
Seat belts................................................465
Clock ......................................................... 456
Coat hooks ..............................................458
Condenser ............................................ 480
Console box ...........................................450
Cooling system ...................................... 478
Engine overheating ..........................587
Hybrid system overheating ..........587
Cruise control
Cruise control ..................................... 253
Dynamic radar cruise control ..... 257
Cup holders ............................................. 451
Current fuel consumption.................. 124
Curtain shield airbags ........................... 43
Customizable features ...................... 608
DAB (Digital Audio Broadcast) ..... 369
Daytime running light system ......... 233
Defogger
Outside rear view mirrors ............ 438
Rear window........................................ 438
Windshield ........................................... 438
Differential............................................... 603
Digital Audio Broadcast (DAB) ..... 369
Dimensions ............................................. 596
Display
Drive information................................. 124
Dynamic radar cruise control ......257
LDA (Lane Departure Alert) ....... 274
Multi-information display................... 121
Warning message ............................ 542
Distance ..................................................... 124
Do-it-yourself maintenance ............. 469
Door courtesy lights
Location ................................................. 446
Door lock
Doors......................................................... 144
Smart entry & start system ............. 155
Wireless remote control ................. 138
Doors...........................................................144
Automatic door locking and
unlocking system ............................. 147
Door lock ................................................ 144
Open door warning buzzer .......... 145
Open door warning light .............. 539
Outside rear view mirrors .............. 193
Side windows ........................................ 196
Drive info 1/Drive info 2 ......................126
Drive information ................................... 124
Resetting .................................................. 124
D

628Alphabetical index
RC300h_EE(OM24740E)
If your vehicle has to be
stopped in an emergency..........529
If your vehicle needs to
be towed............................................ 530
If your vehicle overheats ................587
Energy monitor....................................... 129
Engine....................................................... 598
ACCESSORY mode .......................216
Compartment...................................... 473
Engine switch.........................................215
Hood .......................................................... 471
How to start the hybrid system.....215
Identification number ....................... 597
If the hybrid system will not
start ........................................................ 576
Ignition switch (power switch) ......215
Overheating .........................................587
Power switch .........................................215
Engine coolant ....................................... 478
Capacity .................................................. 601
Checking ............................................ 478
Preparing and checking
before winter .................................... 337
Engine coolant temperature
gauge.........................................................115
Engine oil.................................................. 474
Capacity ................................................ 599
Checking ............................................... 474
Preparing and checking
before winter .................................... 337
Engine oil maintenance data............ 476
Engine switch .......................................... 215
EPS (Electric Power Steering)........304
Warning light ...................................... 538
EV drive mode ....................................... 220
EV indicator ............................................. 126
First-aid kit storage belt ..................... 452
Flat tire
Vehicles with emergency
tire puncture repair kit ................. 563
Floor mats ................................................... 34
Fluid
Brake ....................................................... 603
Hybrid transmission ......................... 602
Washer...................................................480
Fog lights .................................................. 239
Replacing light bulbs ....................... 525
Switch ...................................................... 239
Follow me home system .................... 233
Footwell light .......................................... 446
Wattage .................................................605
Front fog lights ....................................... 239
Replacing light bulbs ....................... 525
Switch ...................................................... 239
Front personal lights............................ 448
Front position lights ............................. 232
Light switch............................................232
Replacing light bulbs ....................... 525
Front seats .................................................178
Adjustment ............................................. 178
Cleaning ................................................ 464
Correct driving posture.................... 36
Driving position memory ................ 183
Head restraints .....................................186
Jam protection function ................... 179
Seat heaters.......................................... 445
Seat position memory .......................183
Seat ventilators ................................... 445
Front turn signal lights ........................ 229
Replacing light bulbs ...........520, 525
Turn signal lever..................................229
F