2004 Lexus GX470 tire pressure

STARTING AND DRIVING
417
Brake assist system
When you slam the brakes on, the brake assist system
judges as an emergency stop and provides more powerful
braking for a driver who cannot hold down the brake pedal
firmly.
When you slam the brakes on, more powerful braking will be
applied. At this time, you may hear a sound in the engine
compartment and feel the vibrations of the brake pedal. This
does not indicate a malfunction.
The brake assist system becomes operative after the vehicle
has accelerated to a speed in excess of approximately 10 km/h
(6 mph). It stops operating when the vehicle decelerates to a
speed below approximately 5 km/h (3 mph).
The brake assist system may not work for about 60 seconds
after the engine is started.
For an explanation of this system's warning light, see ABS
warning lightº on page 63.
Drum-in-disc type parking brake system
Your vehicle has a drum-in-disc type parking brake system.
This type of brake system needs bedding-down of the brake
shoes periodically or whenever the parking brake shoes and/or
drums are replaced.
Have your Lexus dealer perform the bedding-down.
TIRE PRESSURE WARNING
SYSTEM
The tire pressure warning system is designed to provide
warning when tire inflation pressure of one or more of
your tires (including the spare tire) is low. The low tire
pressure warning light comes on to inform you that low
tire inflation pressure may hamper driving.

Low tire pressure warning light
This light comes on when the ignition key is turned to the ONº
position. It goes off after a few seconds. This indicates that the
tire pressure warning system is functioning properly.

STARTING AND DRIVING
418If the low tire pressure warning light comes on or blinks,
do the following.
If the warning light comes on:
Stop your vehicle in a safe place as soon as possible and
check that the inflation pressure of all tires (including the
spare tire) is as specified on the tire and loading
information label. (See Checking tire inflation pressureº
on page 557.) If the warning light comes on even after tire
inflation pressure adjustment, you may have a flat tire. If
you have a flat tire, replace it with the spare tire. For
details, see If you have a flat tireº on page 468.
The warning light goes off a few minutes after air is put into the
deflated tire.
This warning light may turn on due to natural causes such as
natural air leaks or tire pressure changes caused by
temperature. In this case, adjusting the tire pressure will turn
off the warning light.
CAUTION
When the low tire pressure warning light comes on,
observe the following instructions:
Depending on the conditions, reduce to an
appropriate speed as soon as possible.
Adjust the tire pressure to the specified level as soon
as possible.
Avoid abrupt steering wheel maneuvering and
braking. Tire deterioration may reduce steering
wheel control and brake effectiveness. This may lead
to serious injury or death.
The tire pressure warning system may not activate
immediately if sudden bursts of air leakage occur.

STARTING AND DRIVING
419
NOTICE
Do not use liquid sealants for a flat tire as air pressure
sensors will be damaged.
When the tires must be repaired or replaced, have
them repaired or replaced by the nearest Lexus
dealer or authorized tire dealer. The tire pressure
sensors will be affected by the installation or removal
of tires.
The tire pressure warning system is not to be used as
a substitute for regular inspections. Be sure to check
the air pressure in the tires on a regular basis.
When the tires must be replaced, replace the
grommets for air pressure sensors as well.
If the warning light blinks:
The tire pressure warning system may be malfunctioning.
Contact your Lexus dealer.System malfunction
The tire pressure warning system does not function
properly under certain circumstances. In the following
cases, the low tire pressure warning light may not come
on even if the tire inflation pressure is low, or it may come
on when the tire inflation pressure is actually normal.
Electric devices or facilities using similar radio wave
frequencies are nearby.
A radio set to similar frequencies is in use.
A lot of snow or ice covers the vehicle, in particular, around
the wheels or wheel housings.
The tires are not equipped with an air pressure sensor.
Tire chains are used.

STARTING AND DRIVING
420Non-genuine Lexus wheels are used.
Although the tires are equipped with air pressure sensors,
the selector switch (see page 425) is set to other tire setting.
CAUTION
The use of non-genuine wheels will cause the air
pressure sensors to transmit the electronic code in
different manner, resulting in the system failure.
The use of different type of tires with genuine wheels
may also cause the malfunction of the system.
CAUTION
When the tire pressure monitoring system warning light
is lit, one or more of your tires is significantly
under-inflated. You should stop and check your tires as
soon as possible, and inflate them to the proper
pressure as indicated on the vehicle's tire information
placard. Driving on a significantly under-inflated tire
causes the tire to overheat and can lead to tire failure.
Under-inflation also reduces fuel efficiency and tire
tread life, and may affect the vehicle's handling and
stopping ability. Each tire, including the spare, should
be checked monthly when cold and set to the
recommended inflation pressure as specified in the
vehicle placard and owner's manual.

STARTING AND DRIVING
424
Replacing tires and wheels
When replacing the wheels, be sure to install air pressure
sensors on the wheels.
There are 3 ways to set up the air pressure sensors:
(a) Remove the sensor from the old wheel and install it to the
new wheel.
(b) Keep the same wheel with air pressure sensor and replace
only the tire.
(c) Use a new wheel and sensor.
You have to register an ID code for a new sensor. Up to 2 sets
of codes can be registered. As one ID for the originally installed
sensor is registered at MAINº of the selector switch, use the
2ndº position to register an ID for the new sensor.
You do not need to re-register the ID code for any other
replacements. For the use of the originally installed tires, put
the selector switch at MAINº and for the use of tires set
purchased later, put the switch at 2ndº. For the sensor
selector switch, see page 425.CAUTION
Have the tires, wheels or sensors replaced and ID
codes registered by a Lexus dealer. If you need
sensors, purchase from a Lexus dealer.
The use of non-genuine wheels will cause the air
pressure sensors to transmit the electronic code in
different manner, resulting in the failure of the
system.

STARTING AND DRIVING
425
Selector switch

1Main position22nd position
The selector switch is located in the lower part of the
driver's side instrument panel.
The ID code is given in the sensor. To activate the air
pressure warning system, it is necessary to register the ID
code of the sensor on the selector switch in the vehicle.
2 sets of ID codes can be registered. The code of the tires
originally installed on the vehicle is registered on the switch at
MAINº. Have a new tires set with new air pressure sensors
registered at 2ndº by Lexus dealer.
ID codes should be registered by Lexus dealer. Once
registered, change the setting position each time you purchase
tires and wheels. Re-registration is not required.
When purchasing new tires, consult your Lexus dealer.
CAUTION
When the tires whose ID code is registered at MAINº
are used, the system does not work properly with the
selector switch set at 2ndº. If the tires whose ID code
is registered at 2ndº are stored nearby, the system will
detect their tire pressure (and vice versa).

DRIVING TIPS
449
Service connector for towing brake controller
Your vehicle is equipped with a service connector for the
towing brake controller as shown. Link the connector to the
towing brake controller via the sub wire harness stored in the
glove box. The detailed explanation of the sub wire harness
circuit is packed together with the sub wire harness. Be sure
to position the towing brake controller where it does not prevent
the driver from operating the pedal. Lexus recommends that
the sub wire harness be stored in the glove box when it is not
in use.
Tires
Ensure that your vehicle's tires are properly inflated. Adjust
the tire pressure to the recommended cold tire pressure
indicated below.
Tire pressure: 220 kPa (2.2 kgf/cm
2 or bar, 32 psi)
The trailer tires should be inflated to the pressure
recommended by the trailer manufacturer in respect to the
total trailer weight.

DRIVING TIPS
453 When restarting out after parking on a slope:
1. With the transmission in Pº position, start the engine. Be
sure to keep the brake pedal depressed.
2. Shift into the 3º, 2º, Lº or Rº position.
3. Release the parking brake and brake pedal and slowly pull
or back away from the wheel blocks. Stop and apply your
brakes.
4. Have someone retrieve the blocks.
CAUTION
Do not exceed 72 km/h (45 mph) or the posted towing
speed limit, whichever is lower. Because instability
(swaying) of a towing vehicle-trailer combination
usually increases as the speed increases, exceeding
72 km/h (45 mph) may cause loss of control.
Slow down and downshift before descending steep
or long downhill grades. Do not make sudden
downshifts.
Avoid holding the brake pedal down too long or too
frequently. This could cause the brakes to overheat
and result in reduced braking efficiency.
HOW TO SAVE FUEL AND MAKE
YOUR VEHICLE LAST LONGER
Improving fuel economy is easy Ð just take it easy. It will help
make your vehicle last longer, too. Here are some specific tips
on how to save money on both fuel and repairs:
Keep your tires inflated at the correct pressure. Check
the pressure every two weeks, or at least once a month.
Underinflation causes tire wear and wastes fuel.
Do not carry unneeded weight in your vehicle. Excess
weight puts a heavier load on the engine, causing greater
fuel consumption.
Avoid lengthy warm-up idling. Once the engine is
running smoothly, begin driving Ð but gently. Remember,
however, that on cold winter days this may take a little
longer.
Always keep the automatic transmission selector lever
in the Dº position when engine braking is not required.
Driving with the overdrive off will reduce the fuel economy.
(For details, see Automatic transmissionº on page 376.)
Accelerate slowly and smoothly. Avoid jackrabbit starts.
Avoid long engine idling. If you have a long wait and you
are not in traffic, it is better to turn off the engine and start
again later.
Avoid engine over-revving. Use a gear position suitable
for the road on which you are traveling.