brake LEXUS RC300 2020 Service Manual

2456-3. Do-it-yourself maintenance
6
Maintenance and care
6-3.Do-it-yourself maintenance
Do-it-yourself service pre-
cautions
If you perform maintenance by
yourself, be sure to follow the cor-
rect procedure as given in these
sections.
Maintenance
ItemsParts and tools
Battery condition
( P.255)
•Warm water
• Baking soda
•Grease
• Conventional
wrench (for terminal
clamp bolts)
Brake fluid level
( P.254)
• SAE J1703 or
FMVSS No.116 DOT
3 brake fluid
• SAE J1704 or FMVSS No.116 DOT
4 brake fluid
•Rag or paper towel
• Funnel (used only for adding brake fluid)
Engine/inter-
cooler coolant
level( P.252)
•“Toyota Super Long
Life Coolant” or a
similar high quality
ethylene gly-
col-based non-sili-
cate, non-amine,
non-nitrite and
non-borate coolant
with long-life hybrid
organic acid tech-
nology
• For the U.S.A.:“Toy- ota Super Long Life
Coolant” is
pre-mixed with 50%
coolant and 50%
deionized water.
•For Canada:“Toyota Super Long Life
Coolant” is
pre-mixed with 55%
coolant and 45%
deionized water.
•Funnel (used only for adding coolant)
Engine oil level
( P.250)
•“Toyota Genuine
Motor Oil” or equiv-
alent
• Rag or paper towel
•Funnel (used only for adding engine oil)
Fuses ( P.269)
•Fuse with same
amperage rating as
original
ItemsParts and tools

2496-3. Do-it-yourself maintenance
6
Maintenance and care
RC350/RC300 AWDFuse boxes ( P.269)
Battery ( P.255)
Engine oil level dipstick ( P.250)
Engine coolant reservoir ( P.252)
Engine oil filler cap ( P.250)
Brake fluid reservoir ( P.254)
Washer fluid tank ( P.256)
Electric cooling fans
Condenser ( P.254)
Radiator ( P.254)
Engine compartment
Components
A
B
C
D
E
F
G
H
I
J

2506-3. Do-it-yourself maintenance
RC300Fuse boxes ( P.269)
Battery ( P.255)
Engine oil level dipstick ( P.250)
Engine oil filler cap ( P.250)
Engine coolant reservoir ( P.252)
Brake fluid reservoir ( P.254)
Washer fluid tank ( P.256)
Electric cooling fans
Condenser ( P.254)
Intercooler radiator ( P.254)
Radiator ( P.254)
Intercooler coolant reservoir ( P.252)
With the engine at operating tempera-
ture and turned off, check the oil level
on the dipstick.
■Checking the engine oil
1 Park the vehicle on level ground.
After warming up the engine and
turning it off, wait more than 5 min-
utes for the oil to drain back into the
bottom of the engine.
A
B
C
D
E
F
G
H
I
J
K
L
Checking and adding the engine
oil

2546-3. Do-it-yourself maintenance
Check the radiator, condenser and
intercooler radiator and clear away
any foreign objects.
If any of the above parts are extremely
dirty or you are not sure of their condi-
tion, have your vehicle inspected by
your Lexus dealer.
■Checking fluid level
The brake fluid level should be
between the “MAX” and “MIN” lines
on the tank.
RC350/RC300 AWD
RC300
■Adding fluid
Make sure to check the fluid type and
prepare the necessary item.
 Fluid type
SAE J1703 or FMVSS No.116 DOT 3
brake fluid
SAE J1704 or FMVSS No.116 DOT 4
brake fluid
Item
Clean funnel
WARNING
■When the engine is hot
Do not remove the engine coolant reser-
voir cap, intercooler coolant reservoir
cap and coolant inlet cap. ( P.314)
The cooling system may be under pres-
sure and may spray hot coolant if the cap
is removed, causing serious injuries, such
as burns.
NOTICE
■When adding coolant
Coolant is neither plain water nor
straight antifreeze. The correct mixture
of water and antifreeze must be used to
provide proper lubrication, corrosion
protection and cooling. Be sure to read
the antifreeze or coolant label.
■If you spill coolant
Be sure to wash it off with water to pre-
vent it from damagi ng parts or paint.
Checking the radiator, con-
denser and intercooler radiator
(if equipped)
WARNING
■When the engine is hot
Do not touch the radiator, condenser or
intercooler radiator as they may be hot
and cause serious injuries, such as burns.
Checking and adding the brake
fluid

2556-3. Do-it-yourself maintenance
6
Maintenance and care
■Brake fluid can absorb moisture from
the air
Excess moisture in the brake fluid can cause
a dangerous loss of braking efficiency. Use
only newly opened brake fluid.
Check the battery as follows.
■Battery exterior
Make sure that the battery terminals
are not corroded and that there are no
loose connections, cracks, or loose
clamps. Terminals
Hold-down clamp
■Before recharging
When recharging, the battery produces
hydrogen gas which is flammable and
explosive. Therefore, observe the following
before recharging:
●If recharging with the battery installed on
the vehicle, be sure to disconnect the
ground cable.
●Make sure the power switch on the char-
ger is off when connecting and discon-
necting the charger cables to the battery.
■After recharging/reconnecting the bat-
tery
The engine may not start. Follow the proce-
dure below to initialize the system.
1
Shift the shift lever to P.
2
Open and close either door.
3
Restart the engine.
●Unlocking the doors using the smart
access system with pu sh-button start may
not be possible immediately after recon-
necting the battery. If this happens, use
the wireless remote control or the
mechanical key to lock/unlock the doors.
●Start the engine with the engine switch in
ACCESSORY mode. The engine may
not start with the engine switch turned off.
However, the engine will operate nor-
mally from the second attempt.
●The engine switch mode is recorded by
the vehicle. If the battery is disconnected
and reconnected, the vehicle will return
the engine switch mode to the status it
was in before the battery was discon-
nected. Make sure to turn off the engine
before disconnecting the battery. Take
extra care when connecting the battery if
the engine switch mode prior to the bat-
tery being disconnected is unknown.
If the system will not start even after multi-
ple attempts, contact your Lexus dealer.
WARNING
■When filling the reservoir
Take care as brake fluid can harm your
hands and eyes and damage painted sur-
faces.If fluid gets on your hands or in your
eyes, flush the affected area with clean
water immediately.
If you still experience discomfort, see a
doctor.
NOTICE
■If the fluid level is low or high
It is normal for the brake fluid level to go
down slightly as the brake pads wear out
or when the fluid level in the accumulator
is high.
If the reservoir need s frequent refilling,
there may be a serious problem.
Battery
A
B

2767-1. Essential information
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

2777-1. Essential information
7
When trouble arises
seconds or more, or press it briefly
3 times or more in succession.
5
Stop the vehicle in a safe place by
the road. 
Remove the seat belt first.
 If the door can be opened, open the
door and exit the vehicle.
 If the door can not be opened, open
the window using the power window
switch and exit the vehicle through
the window.
 If the window can not be opened
using the power window switch,
remain calm, wait until the water
level inside the vehicle rises to the
point that the water pressure inside
of the vehicle equals the water pres-
sure outside of the vehicle, and then
open the door and exit the vehicle.
WARNING
■If the engine has to be turned off while
driving
Power assist for the brakes and steering
wheel will be lost, making the brake
pedal harder to depress and the steering
wheel heavier to turn. Decelerate as
much as possible before turning off the
engine.
If the vehicle is trapped in
r
ising water
In the event the vehicle is sub-
merged in water, remain calm and
perform the following.
WARNING
■Using an emergency hammer* for
emergency escape
The front side window s and rear window
of this vehicle can be shattered by an
emergency hammer
* used for emer-
gency escape. However, an emergency
hammer
* can not shatter the windshield
as it is laminated glass.
*: Contact your Lexus dealer or after-
market accessory manufacturer for
further information about an emer-
gency hammer.

2817-2. Steps to take in an emergency
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.296)
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

2827-2. Steps to take in an emergency
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.130
■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.296)
 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

2837-2. Steps to take in an emergency
7
When trouble arises
Vehicle pulls heavily to one side
when driving on a level road
 Loss of brake effectiveness, spongy
feeling, pedal almost touches the
floor
Follow the procedure below to restart
the engine after the system is activated.
1
Turn the engine switch to ACCES-
SORY mode or turn it off.
2
Restart the engine.
Fuel pump shut off system
To minimize the risk of fuel leakage
when the engine stalls or when an
airbag inflates upon collision, the
fuel pump shut off system stops the
supply of fuel to the engine.
Restarting the engine
NOTICE
■Before starting the engine
Inspect the ground under the vehicle.
If you find that fuel has leaked onto the
ground, the fuel system has been dam-
aged and is in need of repair. Do not
restart the engine.