2019 LEXUS RC300 ECU

2406-2. Maintenance
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Radiator, con-
denser and inter-
cooler radiator
The radiator, con-
denser and inter-
cooler radiator should
be free from foreign
objects. (P.252)
Washer fluid
Is there sufficient
washer fluid?
( P.254)
Vehicle interior
ItemsCheck points
Accelerator
pedal
• The accelerator
pedal should move
smoothly (without
uneven pedal effort
or catching).
Automatic trans-
mission “Park”
mechanism
•When parked on a slope and the shift
lever is in P, is the
vehicle securely
stopped?
Brake pedal
• Does the brake pedal move
smoothly?
• Does the brake pedal have appro-
priate clearance
from the floor?
• Does the brake pedal have the cor-
rect amount of free
play?
ItemsCheck points
Brakes
• The vehicle should not pull to one side
when the brakes are
applied.
•The brakes should work effectively.
• The brake pedal should not feel
spongy.
• The brake pedal should not get too
close to the floor
when the brakes are
applied.
Head restraints
•Do the head restraints move
smoothly and lock
securely?
Indicators/buzz-
ers•Do the indicators and buzzers function
properly?
Lights• Do all the lights come on?
Parking brake
• Does the parking brake pedal move
smoothly?
• When parked on a slope and the park-
ing brake is on, is the
vehicle securely
stopped?
Seat belts
• Do the seat belts operate smoothly?
• The seat belts should not be damaged.
ItemsCheck points

2726-3. Do-it-yourself maintenance
RC350AWD_RC350_RC300AWD_RC30
0_OM_(U)_1810there is no light leaking from the bulb base.
8Align the tabs and push the light
unit toward the front of the vehicle
to install it.
9
Install the 2 screws and cover.
1
0Remove the protective tape.
WARNING
■Replacing light bulbs
●Turn off the lights. Do not attempt to
replace the bulb immediately after
turning off the lights. The bulbs
become very hot and may cause
burns.
●Do not touch the glass portion of the
light bulb with bare hands. When it is
unavoidable to hold the glass portion,
use and hold with a clean dry cloth to
avoid getting moisture and oils on the
bulb. Also, if the bulb is scratched or
dropped, it may blow out or crack.
●Fully install light bulbs and any parts
used to secure them. Failure to do so
may result in heat damage, fire, or
water entering the lig ht unit. This may
damage the lights or cause condensa-
tion to build up on the lens.
■To prevent damage or fire
●Make sure bulbs are fully seated and
locked.
●Check the wattage of the bulb before
installing to prevent heat damage.

2747-1. Essential information
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7-1.Essential information
Press the switch to flash all of the turn
signal lights.
To turn them off, press the switch once
again.
■Emergency flashers
If the emergency flashers are used for a
long time while the engine is not operating,
the battery may discharge.
1 Steadily step on the brake pedal
with both feet and firmly depress it.
Do not pump the brake pedal repeatedly
as this will increase the effort required to
slow the vehicle.
2Shift the shift lever to N.
If the shift lever is shifted to N
3 After slowing down, stop the vehi-
cle in a safe place by the road.
4 Stop the engine.
If the shift lever cannot be shifted to
N
3 Keep depressing the brake pedal
with both feet to reduce vehicle
speed as much as possible.
4 To stop the engine, press and hold
the engine switch for 2 consecutive
Emergency flashers
The emergency flashers are used to
warn other drivers when the vehicle
has to be stopped on the road due
to a breakdown, etc.
Operating instructions
If your vehicle has to be
stopped in an emergency
Only in an emergency, such as if it
becomes impossible to stop the
vehicle in the normal way, stop the
vehicle using the following proce-
dure:
Stopping the vehicle

2777-2. Steps to take in an emergency
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7
When trouble arises
7-2.Steps to take in an emergency
If your vehicle needs to be
t
owed
If towing is ne cessary, we recom-
mend having your vehicle towed by
your Lexus dealer or commercial
towing service, using a wheel-lift
type truck or flatbed truck.
Use a safety chain system for all
towing, and abide by all state/pro-
vincial and local laws.
WARNING
Observe the following precautions.
Failure to do so may result in death or
serious injury.
■When towing the vehicle
2WD models
Be sure to transport the vehicle with all
four wheels raised off the ground. If the
vehicle is towed with the tires contacting
the ground, the drivetrain and related
parts may be damaged or an accident
may occur due to a change in direction
of the vehicle.
AWD models
Be sure to transport the vehicle with all
four wheels raised off the ground. If the
vehicle is towed with the tires contacting
the ground, the driv etrain or related
parts may be damaged, the vehicle may
fly off the truck.
■While towing
●When towing using cables or chains,
avoid sudden starts, etc. which place
excessive stress on the towing eyelets,
cables or chains. The towing eyelets,
cables or chains may become dam-
aged, broken debris may hit people,
and cause serious damage.
●Do not turn the engine switch off.
There is a possibility that the steering
wheel is locked and cannot be oper-
ated.
■Installing towing eyelets to the vehi-
cle
Make sure that towing eyelets are
installed securely.
If not securely installed, towing eyelets
may come loose during towing.

2787-2. Steps to take in an emergency
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The following may indicate a problem
with your transmission. Contact your
Lexus dealer or commercial towing
service before towing.
The engine is running but the vehi-
cle does not move.
 The vehicle makes an abnormal
sound.
Do not tow with a sling-type truck to
prevent body damage.
From the front
Use a towing dolly under the rear
wheels.
From the rear
Use a towing dolly under the front
wheels.
If your vehicle is transported by a flat-
NOTICE
■To prevent damage to the vehicle
when towing using a wheel-lift type
truck
●Do not tow the vehicle from the rear
when the engine switch is off. The
steering lock mechanism is not strong
enough to hold the front wheels
straight.
●When raising the vehicle, ensure ade-
quate ground clearance for towing at
the opposite end of the raised vehicle.
Without adequate clearance, the vehi-
cle could be damaged while being
towed.
■To prevent damage to the vehicle
when towing with a sling-type truck
Do not tow with a sling-type truck, either
from the front or rear.
■To prevent damage to the vehicle
during emergency towing
Do not secure cables or chains to the
suspension components.
Situations when it is necessary to
contact dealers before towing
Towing with a sling-type truck
Towing with a wheel-lift type
truck
Using a flatbed truck

2797-2. Steps to take in an emergency
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7
When trouble arises
bed truck, it should be tied down at the
locations shown in the illustration.
If you use chains or cables to tie down
your vehicle, the angles shaded in
black must be 45°.
Do not overly tighten the tie downs or
the vehicle may be damaged.
If a tow truck is not available in an
emergency, your vehicle may be tem-
porarily towed using cables or chains
secured to the emergency towing eye-
lets. This should only be attempted on
hard surfaced roads for at most 50
miles (80 km) at under 18 mph (30
km/h).
A driver must be in the vehicle to steer
and operate the brakes. The vehicle’s
wheels, drive train, axles, steering and
brakes must be in good condition. 1
Take out the towing eyelet.
(P.294)
2 Remove the eyelet cover using a
flathead screwdriver.
To protect the bodywork, place a rag
between the screwdriver and the vehicle
body as shown in the illustration.
Except F SPORT models
 F SPORT models
3 Insert the towing eyelet into the
hole and tighten partially by hand.
Emergency towing
Emergency towing procedure

2807-2. Steps to take in an emergency
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4Tighten down the towing eyelet
securely using a wheel nut wrench
or hard metal bar.
5 Securely attach cables or chains to
the towing eyelet.
Take care not to damage the vehi-
cle body.
6 Enter the vehicle being towed and
start the engine.
If the engine does not start, turn the
engine switch to IGNITION ON
mode.
7 Shift the shift lever to N and release
the parking brake.
When the shift lever cannot be
shifted: P.129
■While towing
If the engine is not running, the power assist
for the brakes and steering will not function,
making steering and braking more difficult.
■Wheel nut wrench
Wheel nut wrench is installed in trunk.
(  P.294)
 Fluid leaks under the vehicle.
(Water dripping from the air condi-
tioning after use is normal.)
 Flat-looking tires or uneven tire
wear
 Engine coolant temperature gauge
continually points higher than nor-
mal.
 Changes in exhaust sound
 Excessive tire squeal when corner-
ing
 Strange noises related to the sus-
pension system
 Pinging or other noises related to
the engine
 Engine missing, stumbling or run-
ning roughly
 Appreciable loss of power
 Vehicle pulls heavily to one side
when braking
If you think something is
wrong
If you notice any of the following
symptoms, your vehicle probably
needs adjustment or repair. Con-
tact your Lexus dealer as soon as
possible.
Visible symptoms
Audible symptoms
Operational symptoms

2877-2. Steps to take in an emergency
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7
When trouble arises
■Master warning light (warning buzzer)
■Tire pressure warning light
■SRS warning light
This warning light system monitors the air-
bag sensor assembly, fr ont impact sensors,
side impact sensors (door), side impact
sensors (front), side impact sensors (rear),
driver’s seat position sensor, driver’s seat
belt buckle switch, front passenger occu-
pant classification system, “AIR BAG ON”
indicator light, “AIR BAG OFF” indicator
light, front passenger’s seat belt buckle
switch, seat belt pret ensioners, airbags,
interconnecting wiring and power sources.
(  P.29)
■Front passenger detection sensor, seat
belt reminder and warning buzzer
●If luggage is placed on the front passen-
ger seat, the front passenger detection
sensor may cause th e warning light to
flash and the warning buzzer to sound
even if a passenger is not sitting in the
seat.
●If a cushion is placed on the seat, the sen-
sor may not detect a passenger, and the warning light may not operate properly.
■If the malfunction indicator lamp comes
on while driving
First check the following:
●Is the fuel tank empty?
If it is, fill the fuel tank immediately.
●Is the fuel tank cap loose?
If it is, tighten it securely.
The light will go off after several driving
trips.
If the light does not go off even after several
trips, contact your Lexus dealer as soon as
possible.
■Electric power steering system warning
light (warning buzzer)
When the battery charge becomes insuffi-
cient or the voltage temporarily drops, the
electric power steering system warning
light may come on and the warning buzzer
may sound.
Warning lightDetails/Actions
A buzzer sounds and the warning light comes on and flashes to indicate
that the master warning system has detected a malfunction.
 P.290
Warning lightDetails/Actions
When the light comes on:
Low tire inflation pressure such as
Natural causes ( P.288)
 Flat tire ( P.294)
 Adjust the tire inflation pressure to the specified level. The light will
turn off after a few minutes. In case the light does not turn off even if
the tire inflation pressure is adju sted, have the system checked by
your Lexus dealer.
When the light comes on after blinking for 1 minute:
Malfunction in the tire pressure warning system
 Have the system checked by your Lexus dealer.