2018 LEXUS RCF engine overheat

TABLE OF CONTENTS
6
RC350_RC300 AWD_RC3 00_RC F_U(OM24748U)7-1. Essential information
Emergency flashers .................. 442
If your vehicle has
to be stopped in
an emergency .......................... 443
7-2. Steps to take in
an emergency
If your vehicle needs
to be towed ............................... 444
If you think something is
wrong.............................................451
Fuel pump shut off system ...... 452
If a warning light turns on
or a warning buzzer
sounds ......................................... 453
If a warning message is
displayed .................................... 460
If you have a flat tire
(vehicles with a
spare tire) ................................... 489
If you have a flat tire
(vehicles with
an emergency
tire puncture repair kit) ........ 502
If the engine will not start ..........516
If the electronic key does
not operate pr operly .............. 518
If the vehicle battery is
discharged ................................. 522
If your vehicle overheats......... 526
If the vehicle becomes
stuck ............................................. 532 8-1. Specifications
Maintenance data
(fuel, oil level, etc.) .................. 536
Fuel information ......................... 554
Tire information .......................... 557
8-2. Customization
Customizable features ............ 569
8-3. Items to initialize
Items to initialize......................... 578
8-4. Certifications
Certifications ............................... 579
Reporting safety defects for
U.S. owners ...............................600
Seat belt instructions for
Canadian owners
(in French) .................................. 601
SRS airbag instructions for
Canadian owners
(in French) ................................. 6037
When trouble arises 8
Vehicle specifications
9
For owners

15Pictorial index
RC350_RC300 AWD_RC3 00_RC F_U(OM24748U)Doors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 145Locking/unlocking. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 145
Opening/closing the side window . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 182
Locking/unlocking by using the me chanical key . . . . . . . . . . . . . . . . . . . . . . . . P. 518
Warning lights/warning messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .P. 454, 462
Windshield wipers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 233 Precautions against winter season . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 320
To prevent freezing (windshield wiper de-icer)
* . . . . . . . . . . . . . . . . . . . . . . . P. 339
Precautions against car wash . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 378
Fuel filler door . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 241Refueling method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P . 241
Fuel type/fuel tank capacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 540
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 412Tire size/inflation pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 548
Winter tires/tire chain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 32 0
Checking/rotation/tire pressure warning system . . . . . . . . . . . . . . . . . . . . . . . P. 412
Coping with flat tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 489, 502
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 393Opening. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 393
Engine oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 540
Coping with overheating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 526
Warning messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 463
Headlights/turn signal lights/side marker lights . . . . . . . . . . . . . P. 221, 225
Parking lights/daytime running lights. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .P. 225
Front fog lights
* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 232 1
2
3
4
5
Light bulbs of the exte rior lights for driving
(Replacing method: P. 432, Watts: P. 553)
* : If equipped6
7
8

952. Instrument cluster
2
Instrument cluster
RC350_RC300 AWD_RC3 00_RC F_U(OM24748U)■
The meters and display illuminate when
The engine switch is in IGNITION ON mode. ■
Instrument panel brightness adjustment
The instrument panel brightness levels when the tail lights are on and off can be adjusted
individually. However, when the surroundings are bright (dayti me, etc.), turning on the tail
lights will not change the inst rument panel brightness. At th is time, any adjustments made
to the instrument panel brightness levels will be applied to both settings at once. ■
Outside temperature display ●
In the following situations, the correct outside temperature may not be displayed, or the
display may take longer than normal to change.
• When stopped, or driving at low speeds (less than 12 mph [20 km/h])
• When the outside temperature has changed suddenly (at the entrance/exit of a
garage, tunnel, etc.) ●
When “_ _”or “E” is displayed, the system may be malfunctioning.
Take your vehicle to your Lexus dealer. ■
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-info rmation display or the odometer/trip meter
screen (F SPORT models). ●
Some pop-up displays can be set on/off. (  P. 111)■
Customization
The meter display can be customized on the multi-information display. (  P. 111)
NOTICE ■
To prevent damage to the engine and its components●
Do not let the indicator needle of the tachometer enter the red zone, which indicates
the maximum engine speed. ●
The engine may be overheating if the engine coolant temperature gauge is in the red
zone (H). In this case, immediately stop the vehicle in a safe place, and check the
engine after it has cooled completely. (  P. 526)

102 2. Instrument cluster
RC350_RC300 AWD_RC3 00_RC F_U(OM24748U)■
Instrument panel brightness adjustment
The instrument panel brightness levels when the tail lights are on and off can be adjusted
individually. However, when the surroundings are bright (dayti me, etc.), turning on the tail
lights will not change the inst rument panel brightness. At th is time, any adjustments made
to the instrument panel brightness levels will be applied to both settings at once. ■
Dimming the analog speedometer lighting
The analog speedometer lighting will be dimm ed when the ambient light is bright, such
as during the daytime, and SPORT S or SPORT S+ mode is selected.■
Outside temperature display ●
In the following situations, the correct outside temperature may not be displayed, or the
display may take longer than normal to change.
• When stopped, or driving at low speeds (less than 12 mph [20 km/h])
• When the outside temperature has changed suddenly (at the entrance/exit of a
garage, tunnel, etc.) ●
When “  ” or “E” is displayed, the sy stem may be malfunctioning.
Take your vehicle to your Lexus dealer. ■
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.●
Some pop-up displays can be set on/off. (  P. 129)■
Liquid crystal display
Small spots or light spots may appear on the 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. 129)
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. ●
In the following situations, th e engine may be overheating. In this case, immediately
stop the vehicle in a safe place, and check the engine after it has cooled completely.
(  P. 526)
• The engine coolant temperature gauge indicator ( ) is in the red zone and flash-
ing.
• The engine oil temperature gauge indicator ( ) is in the red zone and flashing.

1954-1. Before driving
4
Driving
RC350_RC300 AWD_RC3 00_RC F_U(OM24748U)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 engine running. 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 po sture even when moving the vehicle only
slightly. This allows you to depress th e brake and accelerator pedals properly.
• Depress the brake pedal using your right foot. Depressing the brake pedal using
your left foot may delay re sponse in an emergency, resulting in an accident.●
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 engine. Turning the engi ne off while driving
will not cause loss of steering or braking control, but the power assist to these systems
will be lost. This will make it more difficult to steer and brake, so you should pull over
and stop the vehicle as soon as it is safe to do so.
However, in the event of an emergency, such as if it becomes impossible to stop the
vehicle in the normal way:  P. 443●
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. 213)●
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, he ads or other parts of their body are not
outside the vehicle. ●
Do not drive in excess of the speed limit. Even if the legal speed limit permits it, do not
drive over 85 mph (140 km/h) unless your vehicle has high-speed capability tires.
Driving over 85 mph (140 km/h ) may result in tire failure , loss of control and possible
injury. Be sure to consult a tire dealer to determine whether the tires on your vehicle
are high-speed capability tires or no t before driving at such speeds.

1974-1. Before driving
4
Driving
RC350_RC300 AWD_RC3 00_RC F_U(OM24748U)WARNING
Observe the following precautions.
Failure to do so may result in death or serious injury. ■
If a brake pad wear warning message is displayed (RC F)
Have the brake pads visually checked and replaced by your Lexus dealer as soon as
possible.
Rotor damage may result if the pads are not replaced when needed.
Moderate levels of the brake pad and disc wear allow enhanced braking power. As a
result, the discs may wear more quickly than conventional brake discs. Therefore, when
replacing the brake pads, Lexu s recommends that you also have the thickness of the
discs measured.
It is dangerous to drive the vehicle when the wear limits of the brake pads and/or those
of the brake discs are exceeded. ■
When the vehicle is stopped ●
Do not race the engine.
If the vehicle is in any gear other than P or N, the vehicle may accelerate suddenly
and unexpectedly, causing an accident. ●
In order to prevent accidents due to the ve hicle rolling away, always keep depressing
the brake pedal while the engine is running, and apply the parking brake as neces-
sary. ●
If the vehicle is stopped on an incline, in order to prevent accidents caused by the
vehicle rolling forward or backward, alwa ys depress the brake pedal and securely
apply the parking brake as needed. ●
Avoid revving or r acing the engine.
Running the engine at high speed while the vehicle is stopped may cause the exhaust
system to overheat, which could result in a fire if combustible material is nearby.

210 4-2. Driving procedures
RC350_RC300 AWD_RC3 00_RC F_U(OM24748U)■
Auto power off function
If the vehicle is left in ACCESSORY mode for more than 20 minutes or IGNITION ON
mode (the engine is not running) for more than an hour with the shift lever in P, the engine
switch will automatically turn off. However, this function cannot entirely prevent battery
discharge. Do not leave the vehicle with the engine switch in ACCESSORY or IGNI-
TION ON mode for long periods of ti me when the engine is not running.■
Electronic key battery depletion
 P. 143 ■
Conditions affe cting operation
 P. 158 ■
Notes for the entry function
 P. 159 ■
If the engine does not start ●
Check that the shift lever is se curely set in P. The engine ma y not start if the shift lever is
displaced out of P. ●
The engine immobilizer system ma y not have been deactivated. (  P. 79)
Contact your Lexus dealer. ■
Steering lock
After turning the engine switch off and opening and closing the doors, the steering wheel
will be locked due to the steering lock func tion. Operating the engine switch again auto-
matically cancels the steering lock. ■
When the steering lock cannot be released
■
Steering lock motor overheating prevention
To prevent the steering lock motor from overheating, operation of the motor may be sus-
pended if the engine is turned on and off repeat edly in a short period of time. In this case,
refrain from operating the engine switch. After about 10 seconds, the steering lock
motor will resume functioning. ■
When “Access System with Elec. Key Malf unction See Owner’s Manual” is displayed
on the multi-information display
The system may be malfunctio ning. Have the vehicle inspected by your Lexus dealer
immediately. ■
If the electronic key battery is depleted
 P. 427“Steering Wheel Lock Press Engine Switch
while Turning Wheel” w ill be displayed on the
multi-information display.
Check that the shift leve r is in P. Press the
engine switch while turn ing the steering wheel
left and right.

3174-5. Using the driving support systems
4
Driving
RC350_RC300 AWD_RC3 00_RC F_U(OM24748U)■
Sounds and vibrations caused by the ABS, brake assist, VSC, TRAC, hill-start assist
control and VGRS systems ●
A sound may be heard from the engine compartment when the brake pedal is
depressed repeatedly, when the engine is started or just after the vehicle begins to
move. This sound does not indicate that a malfunction has occurred in any of these sys-
tems. ●
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 afte r the vehicle comes to a stop.
• The brake pedal may pulsate slig htly after the ABS is activated.
• The brake pedal may move down s lightly after the ABS is activated.■
EPS, VGRS and DRS operation sound
When the steering wheel is operated, a motor sound (whirring sound) may be heard.
This does not indicate a malfunction. ■
Reactivation of the TRAC/VSC systems
Even after the TRAC/VSC systems have been turned off, turning the engine off and then
on again will automatically reactivate the TRAC/VSC systems. ■
Reactivation of the TRAC sy stem linked to vehicle speed
When only the TRAC system is turned off, the TRAC system will turn on when vehicle
speed increases. However, wh en both TRAC/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 reduced to prevent the system from overheating
when there is frequent steering input over an extended period of time. The steering
wheel may feel heavy as a result . Should this occur, refrain from excessive steering input
or stop the vehicle and turn the engine off. The EPS system should return to normal
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 af ter the brake pedal is released.