1994-5. Using the driving support systems
RC350/RC300 Owner's Manual
4
Driving
■TRAC (Traction Control)
Helps to maintain drive power and pre-
vent the drive wheels from spinning
when starting the vehicle or accelerat-
ing on slippery roads
■Hill-start assist control
Helps to reduce the backward move-
ment of the vehicle when starting on an
uphill
■VGRS (Variable Gear Ratio Steer-
ing) (if equipped)
Adjusts the front wheel turning angle in
accordance with the vehicle speed and
steering wheel movement
■DRS (Dynamic Rear Steering) (if
equipped)
Contributes to the turning characteris-
tics and responsiveness of the vehicle
by adjusting the rear wheel angle of the
vehicle in accordance with steering
wheel movement.
■EPS (Electric Power Steering)
Employs an electric motor to reduce
the amount of effort needed to turn the
steering wheel
■Adaptive Variable Suspension Sys-
tem (if equipped)
By independently controlling the
damping force of the shock absorbers
for each of the 4 wheels according to
the road and driving conditions, this
system combines riding comfort with
superior vehicle stability, and helps
good vehicle posture.
■LDH (Lexus Dynamic Handling
system) (if equipped)
Provides integrated control of the
VGRS, DRS and EPS. Contributes to
turning characteristics at low speeds,
responsiveness at medium speeds and
safety at high speeds by controlling the
steering angle of the front and rear
wheels in accordance with the steering
wheel operation and vehicle speed.
■VDIM (Vehicle Dynamics Inte-
grated Management)
Provides integrated control of the
ABS, brake assist, TRAC, VSC,
hill-start assist control, EPS and VGRS
systems
Helps to maintain vehicle stability when
swerving on slippery road surfaces by
controlling the brakes, engine output,
steering assist, and steering ratio
■When the TRAC/VSC systems are
operating
The slip indicator light will flash while the
TRAC/VSC systems are operating.
■Disabling the TRAC system
If the vehicle gets stuck in mud, dirt or snow,
the TRAC system may reduce power from
the engine to the wheels. Pressing the
switch to turn the system off may make it
easier for you to rock the vehicle in order to
free it.
To turn the TRAC system off, quickly press
2014-5. Using the driving support systems
RC350/RC300 Owner's Manual
4
Driving
ever, the position will return to normal after
VGRS is reactivated.
■When the battery is disconnected (vehi-
cles with VGRS)
The steering wheel may move from its
straight forward position, but this will be
corrected automatically when driving.
■Sounds and vibrations caused by the
ABS, brake assist, VS C, 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
systems.
●Any of the following conditions may
occur when the above systems are oper-
ating. None of these indicates that a mal-
function has occurred.
• Vibrations may be felt through the vehicle body and steering.
• A motor sound may be heard also after the vehicle comes to a stop.
• The brake pedal may pulsate slightly after
the ABS is activated.
• The brake pedal may move down slightly after the ABS is activated.
■EPS, VGRS and DR S operation sound
When the steering wheel is operated, a
motor sound (whirring sound) may be
heard. This does not indicate a malfunction.
■Automatic reactivation of TRAC/VSC
systems
After turning the TRAC and VSC systems
off, the systems w ill be automatically
re-enabled in the following situations:
●When the engine switch is turned off
●If only the TRAC system is turned off, the
TRAC will turn on when vehicle speed
increases
If both the TRAC and VSC systems are
turned off, automatic re-enabling will not
occur when vehicle speed increases.
■Reduced effectiveness of the EPS sys-
tem
The effectiveness of the EPS system is
reduced to prevent the system from over-
heating when there is frequent steering
input over an extended period of time. The
steering wheel may feel heavy as a result.
Should this occur, re frain from excessive
steering input or stop the vehicle and turn
the engine off. The EPS system should
return to normal within 10 minutes.
WARNING
■The ABS does not operate effectively
when
●The limits of tire gripping performance
have been exceeded (such as exces-
sively worn tires on a snow covered
road).
●The vehicle hydroplanes while driving
at high speed on wet or slick roads.
■Stopping distance when the ABS is
operating may exceed that of normal
conditions
The ABS is not designed to shorten the
vehicle’s stopping di stance. Always main-
tain a safe distance from the vehicle in
front of you, especially in the following
situations:
●When driving on dirt, gravel or
snow-covered roads
●When driving with tire chains
●When driving over bumps in the road
●When driving over roads with potholes
or uneven surfaces
■TRAC/VSC may not operate effec-
tively when
Directional control and power may not
be achievable while driving on slippery
road surfaces, even if the TRAC/VSC
system is operating. Drive the vehicle
carefully in conditions where stability and
power may be lost.
2024-5. Using the driving support systems
RC350/RC300 Owner's Manual
WARNING
■Hill-start assist control does not oper-
ate effectively when
●Do not overly rely on hill-start assist
control. Hill-start assist control may
not operate effectively on steep
inclines and roads covered with ice.
●Unlike the parking brake, hill-start
assist control is not intended to hold
the vehicle stationary for an extended
period of time. Do not attempt to use
hill-start assist control to hold the vehi-
cle on an incline, as doing so may lead
to an accident.
■When the TRAC/VSC is activated
The slip indicator light flashes. Always
drive carefully. Re ckless driving may
cause an accident. Exercise particular
care when the indicator light flashes.
■When the TRAC/VSC systems are
turned off
Be especially careful and drive at a speed
appropriate to the road conditions. As
these are the systems to help ensure
vehicle stability and driving force, do not
turn the TRAC/VSC systems off unless
necessary.
■Replacing tires
Make sure that all ti res are of the speci-
fied size, brand, tread pattern and total
load capacity. In addition, make sure that
the tires are inflated to the recom-
mended tire inflation pressure level.
The ABS, TRAC and VSC systems will
not function correctly if different tires are
installed on the vehicle.
Contact your Lexus dealer for further
information when replacing tires or
wheels.
■Handling of tires and the suspension
Using tires with any kind of problem or
modifying the suspension will affect the
driving assist systems, and may cause a
system to malfunction.
2616-3. Do-it-yourself maintenance
RC350/RC300 Owner's Manual
6
Maintenance and care
■Brake fluid can absorb moisture from
the air
Excess moisture in the brake fluid can cause
a dangerous loss of br aking 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 th e 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 push-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 lo ck/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
2736-3. Do-it-yourself maintenance
RC350/RC300 Owner's Manual
6
Maintenance and careUse only Lexus wheel nuts and
wrenches designed for use with
your aluminum wheels.
When rotating, repairing or chang-
ing your tires, check that the wheel
nuts are still tight after driving 1000
miles (1600 km).
Be careful not to damage the alumi-
num wheels when using tire chains.
Use only Lexus genuine balance
weights or equivalent and a plastic
or rubber hammer when balancing
your wheels. 1
Turn the engine switch off.
2 Open the glove box. Lift up the side
with the stay, disconnect the stay
tabs and remove the partition by
pulling horizontally.
3 Press the tabs and remove the filter
cover.
WARNING
●Never use an inner tube in a leaking
wheel which is designed for a tubeless
tire. Doing so may result in an acci-
dent, causing death or serious injury.
NOTICE
■Replacing tire pressure warning
valves and transmitters
●Because tire repair or replacement
may affect the tire pressure warning
valves and transmitters, make sure to
have tires serviced by your Lexus
dealer or other qual ified service shop.
In addition, make sure to purchase
your tire pressure warning valves and
transmitters at your Lexus dealer.
●Ensure that only ge nuine Lexus wheels
are used on your vehicle.
Tire pressure warning valves and trans-
mitters may not work properly with
non-genuine wheels.
Aluminum wheel precautions
Air conditioning filter
The air conditioning filter must be
changed regularly to maintain air
conditioning efficiency.
Removing the air conditioning
filter
2746-3. Do-it-yourself maintenance
RC350/RC300 Owner's Manual
4Press the tabs and remove the filter
case.
5 Remove the air conditioning filter
from the filter case and replace it
with a new one.
The “ UP” marks shown on the filter
and the filter case should be pointing up.
■Checking interval
Inspect and replace the air conditioning fil-
ter according to the maintenance schedule.
In dusty areas or area s with heavy traffic
flow, early replacement may be required.
(For scheduled mainte nance information,
please refer to the “Owner’s Manual Sup-
plement” or “Scheduled Maintenance”.)
■If air flow from th e vents decreases dra-
matically
The filter may be clogged. Check the filter
and replace if necessary.
■Air conditioning filter with deodorizing
function
When fragrances are placed in your vehi-
cle, the deodorizing effect may become
significantly weakened in a short period. When an air conditioning odor comes out
continuously, replace the air conditioning
filter.
NOTICE
■When using the air conditioning sys-
tem
Make sure that a filter is always installed.
Using the air conditioning system without
a filter may cause damage to the system.
2816-3. Do-it-yourself maintenance
RC350/RC300 Owner's Manual
6
Maintenance and care
4Pull the light unit toward the rear of
the vehicle to remove it.
5 Turn the bulb base
counterclockwise.
6 Remove the light bulb.
7 Install a new light bulb then install
the bulb base to the light unit by
inserting it and turning the bulb
base clockwise.
After installing the light bulb, turn on the
rear turn signal light to visually check that there is no light leaking from the bulb base.
8
Align the tabs and push the light
unit toward the front of the vehicle
to install it.
9 Install the 2 screws and cover.
10 Remove 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 bu lb is scratched or
dropped, it may blow out or crack.
2957-2. Steps to take in an emergency
RC350/RC300 Owner's Manual
7
When trouble arises
■ABS warning light
■Brake Override System warning light/Drive-Start Control warning light*
(warning buzzer)
*: This light illuminates on th e multi-information display.
■Electric power steering system warning light (warning buzzer)
Warning lightDetails/Actions
(U.S.A.)
or
(Canada)
Indicates a malfunction in:
The ABS; or
The brake assist system
Have the vehicle inspected by your Lexus dealer immediately.
Warning lightDetails/Actions
When a buzzer sounds:
Brake Override System is malfunctioning;
Drive-Start Control is operating; or
Drive-Start Control is malfunctioning
Follow the instructions displayed on the multi-information display.
When a buzzer does not sound:
Brake Override System is operating
Release the accelerator pedal and depress the brake pedal.
Warning lightDetails/Actions
Indicates a malfunction in the EPS (Electric Power Steering) system
Have the vehicle inspected by your Lexus dealer immediately.