air suspension Lexus GX470 2004 Audio System / LEXUS 2004 GX470 FROM NOV. 2003 THROUGH DEC. 2003 PROD. (OM60A74U) User Guide

STARTING AND DRIVING
398
NOTICE
If the vehicle height is changed frequently when the
vehicle is heavily loaded, the compressor may
overheat causing the vehicle height adjustment
operation to stop.
Before you lower the vehicle height with the height
select switch, check under the vehicle to make sure
nothing to damage the vehicle or no one to be injured
is there and that the underbody of the vehicle does
not touch the ground.
After unloading, the height of a vehicle equipped with
the rear height control air suspension becomes
slightly higher than the normal vehicle height. Take
sufficient care where the overhead height is
restricted.
Do not select the LOº mode in the bumpy roads. If
the underbody of the vehicle touches the rugged
road surface, the vehicle may be damaged.

STARTING AND DRIVING
399
(d) Turning off the rear height control air
suspension
To turn off the rear height control air suspension with the
vehicle stopped, push the HEIGHT CONTROL OFFº
switch. The height control OFFº indicator light comes on
and the vehicle height is fixed in the same mode as the
height control switch is pushed.
This status is memorized in the system even after the engine
is stopped.
If you push the switch again, the height control OFFº indicator
light goes out and the rear height control air suspension is
turned on.
Even after the rear height control air suspension is turned off
with the HEIGHT CONTROL OFFº switch, if the vehicle speed
exceeds 30 km/h (19 mph), the rear height control air
suspension automatically selects the Nº mode.
CAUTION
If you drive through deep water over about 700 mm (28
in.) in depth, put the vehicle height in the HIº mode with
the height select switch and then turn off the rear height
control air suspension by pushing the HEIGHT
CONTROL OFFº switch.

STARTING AND DRIVING
400
NOTICE
When jacking up or installing tire chains, be sure to
turn off the rear height control air suspension with
the HEIGHT CONTROL OFFº switch and stop the
engine. Otherwise, the vehicle height may change
because of the automatic leveling function resulting
in accident.
If your vehicle must be towed, put the vehicle height
in the Nº mode and turn off the rear height control air
suspension. Otherwise, the vehicle height may
change because of the automatic leveling function
resulting in accident.
If your vehicle gets ditched, turn off the rear height
control air suspension with the HEIGHT CONTROL
OFFº switch. Otherwise, the vehicle height may
change because of the automatic leveling function
resulting in accident.

STARTING AND DRIVING
401
(e) Height control indicator lights

1Height control indicator lights
2Height control OFFº indicator light
When the ignition switch is turned on, all the indicator lights
come on. Only the indicator light showing the present mode
remains on and all other lights go off after a few seconds. This
means the system operates correctly.
When you change the vehicle height mode, the indicator lights
change as follows:
When changing the vehicle height from the Nº mode to
HIº:
1. The Nº mode indicator light goes off and the HIº mode
indicator light blinks.
2. After the vehicle height control reaches the HIº mode, the
HIº mode indicator light remains on.If the underbody of the vehicle has touched the surface on
bumpy roads or the area around the rear suspension is
coated with ice, the height control suspension will not
operate and the indicator lights change as follows:
1. The present mode indicator light goes off and the selected
mode indicator light blinks.
2. The selected mode indicator light goes off. (The vehicle
height does not change.) The present mode indicator light
comes on again.
Height control OFFº indicator light: When the ignition
switch is turned on, this light comes on. If it goes out after a few
seconds, the rear height control air suspension operates
correctly. If you push the HEIGHT CONTROL OFFº switch,
the rear height control air suspension is turned off. The height
control OFFº indicator light comes on.
In the following cases, there is a problem somewhere in the
rear height control air suspension. Although there is no
problem to continue normal driving, have the rear height
control air suspension checked by your Lexus dealer as soon
as possible.
The height control OFFº indicator light does not come on
when the ignition switch is turned on.
The height control OFFº indicator light blinks.

STARTING AND DRIVING
402
(f) Parking and stopping tips
If you immediately stop the engine to park the vehicle after
off-road driving, the vehicle height is lowered slightly as the
vehicle becomes cool. When parking, make sure there is
nothing that will be in contact with the underbody of the vehicle.
When you start the engine, the vehicle returns to the previous
height.
If you park the vehicle for a long time, the vehicle height may
be gradually lowered. When parking for a long time, make sure
there is nothing that will be in contact with the underbody of the
vehicle. When you start the engine, the vehicle returns to the
previous height.
If you stop the engine, the vehicle height may change in
accordance with the change in the temperature. When you
start the engine, the vehicle returns to the previous height.
(g) Rear height control failure warning
If there is a problem somewhere in the rear height control air
suspension, the Nº mode is automatically selected. If this
occurs, the height control OFFº indicator light blinks and the
vehicle height control cannot be activated until the malfunction
is corrected. If this is the case, bring your vehicle to your Lexus
dealer as soon as possible and have it checked.
ELECTRONIC MODULATED
SUSPENSION
This electronic modulated suspension adjusts the
damping effect on the shock absorbers with the control
switch. Select one of the 4 modes which is suited to the
driving conditions with the control switch to provide good
riding comfort and stability.
1For driving on a bumpy road
2For ordinary driving such as in the city traffic
3For moderate high speed driving
4For sporty type driving such as on winding mountain
roads and high speed driving
5Soft
6Firm
We recommend you to select the mode 2
for ordinary
driving. The damping effect will be changed automatically to
provide good riding comfort.

DRIVING TIPS
441
TRAILER TOWING
Your vehicle is designed primarily as a passenger-and-load
carrying vehicle. Towing a trailer will have an adverse effect on
handling, performance, braking, durability and driving
economy (fuel consumption, etc.). Your safety and satisfaction
depend on the proper use of correct equipment and cautious
driving habits. For your safety and the safety of others, you
must not overload your vehicle or trailer. Lexus warranties do
not apply to damage or malfunction caused by towing a trailer
for commercial purposes. Ask your local Lexus dealer for
further details before towing.
CAUTION
When disconnecting a trailer, put the vehicle height in
the LOº (low) mode and push the HEIGHT CONTROL
OFFº switch to turn off the rear height control air
suspension. Otherwise, the vehicle height may be
changed in the automatic leveling function, resulting in
accident. For details see Rear height control air
suspensionº on page 395.
Weight limits
Before towing, make sure the total trailer weight, gross
vehicle weight, gross axle weight and trailer tongue load
are all within the limits.
The total trailer weight and tongue load can be measured with
platform scales found at a highway weighing station, building
supply company, trucking company, junk yard, etc.

Certification label

DRIVING TIPS
450
Trailer lights
Your vehicle is equipped with a wire harness stored in the rear
end underbody. Use either of them to connect and operate the
trailer lights. However, the trailer lights must comply with
federal, state/provincial and local regulations. See your local
recreational vehicle dealer or rental agency for the correct type
of wiring and relays for your trailer. Check for correct operation
of the turn signals and stop lights each time you hitch up. Direct
splicing may damage your vehicle's electrical system and
cause a malfunction of your lights.
Break-in schedule
Lexus recommends that you do not tow a trailer with a new
vehicle or a vehicle with any new power train component
(engine, transmission, differential, wheel bearing, etc.) for the
first 800 km (500 miles) of driving.
Maintenance
If you tow a trailer, your vehicle will require more frequent
maintenance due to the additional load. For this
information, please refer to the scheduled maintenance
information in the Owner's Manual Supplement/Scheduled
Maintenanceº.
Retighten all fixing bolts of the towing ball and bracket after
approximately 1000 km (600 miles) of trailer driving.
Connecting a trailer
Stop your vehicle and a trailer in line and perform the following:
1. Put the rear height control air suspension in the LOº (low)
mode. Turn the ignition switch off or push the HEIGHT
CONTROL OFFº switch to turn off the rear height control air
suspension.
2. Connect a trailer.
3. Turn the ignition switch on or push the HEIGHT CONTROL
OFFº switch to turn on the rear height control air suspension.
Select the Nº (normal) mode with the height select switch.
Disconnecting a trailer
Stop your vehicle and a trailer in line and perform the following:
1. Put the rear height control air suspension in the LOº (low)
mode. (Make sure the vehicle height is in the LOº (low) mode
by pushing the height select switch on the º side.)
2. Turn the ignition switch off or push the HEIGHT CONTROL
OFFº switch to turn off the rear height control air suspension.
3. Set the supporting leg of a trailer on the ground and raise the
hitch by 100 mm (4 in.).
4. Turn the ignition switch on or push the HEIGHT CONTROL
OFFº switch to turn on the rear height control air suspension.
5. Wait for about 20 seconds until the rear vehicle height is
lowered by the automatic leveling function.
6. Make sure the hitch is disconnected. If not, raise the hitch
higher and repeat steps 2 through 5.

DRIVING TIPS
451 7. Move the vehicle forward in the LOº (low) mode where the
hitch does not touch anything in the Nº (normal) mode.
8. Put the rear height control air suspension in the Nº (normal)
mode.
Pre-towing safety check
Check that your vehicle remains level when a loaded or
unloaded trailer is hitched. Do not drive if the vehicle has an
abnormal nose-up or nose-down condition, and check for
improper tongue load, overload, worn suspension or other
possible causes.
Make sure the trailer cargo is securely loaded so that it
cannot shift.
Check that your rear view mirrors conform to any federal,
state/provincial or local regulations. If they do not, install
required rear view mirrors appropriate for towing purposes.
Trailer towing tips
When towing a trailer, your vehicle will handle differently
than when not towing. The three main causes of
vehicle-trailer accidents are driver error, excessive speed
and improper trailer loading. Keep these in mind when
towing:
Before starting out, check the operation of the lights and all
vehicle-trailer connections. After driving a short distance,
stop and recheck the lights and connections. Practice
turning, stopping and backing with a trailer in an area away
from traffic until you learn the feel.
Backing with a trailer is difficult and requires practice. Grip
the bottom of the steering wheel and move your hand to the
left to move the trailer to the left. Move your hand to the right
to move the trailer to the right. (This procedure is generally
opposite to that when backing without a trailer.) Also, just
turn the steering wheel a little at a time, avoiding sharp or
prolonged turning. Have someone guide you when backing
to reduce the risk of an accident.
Because stopping distance may be increased,
vehicle-to-vehicle distance should be increased when
towing a trailer. For each 16 km/h (10 mph) of speed, allow
at least one vehicle and trailer length between you and the
vehicle ahead. Avoid sudden braking as you may skid,
resulting in jackknifing and loss of control. This is especially
true on wet or slippery surfaces.
Avoid jerky starts or sudden acceleration.
Avoid jerky steering and sharp turns. The trailer could hit
your vehicle in a tight turn. Slow down before making a turn
to avoid the need of sudden braking.

IN CASE OF AN EMERGENCY
470
NOTICE
Do not continue driving with a deflated tire.
Driving even a short distance can damage a
tire and wheel beyond repair.
When jacking up or installing tire chains, be
sure to turn off the rear height control air
suspension with the HEIGHT CONTROL
OFFº switch and stop the engine. Otherwise,
the vehicle height may change because of the
automatic leveling function resulting in
accident.

IN CASE OF AN EMERGENCY
484
IF YOUR VEHICLE NEEDS TO BE
TOWED
If towing is necessary, we recommend you to have it done
by your Lexus dealer or a commercial tow truck service.
In consultation with them, have your vehicle towed using
either (a) or (b).
(a) Towing with a wheel lift type truck
(b) Using a flat bed truck
(c) Never tow with a sling type truck
Only when you cannot receive a towing service from a
Lexus dealer or commercial tow truck service, tow your
vehicle carefully in accordance with the instructions
given in (d) Emergency towingº on page 489.
Proper equipment will help ensure that your vehicle is not
damaged while being towed. Commercial operators are
generally aware of the state/provincial and local laws
pertaining to towing.
Your vehicle can be damaged if it is towed incorrectly. Although
most operators know the correct procedure, it is possible to
make a mistake. To avoid damage to your vehicle, make sure
the following precautions are observed. If necessary, show
this page to the tow truck driver.TOWING PRECAUTIONS:
Use a safety chain system for all towing, and abide by the
state/provincial and local laws. The wheels and axle on the
ground must be in good condition. If they are damaged, use
a towing dolly.
CAUTION
When your vehicle is towed, put the vehicle height in the
Nº (normal) mode and push the HEIGHT CONTROL
OFFº switch to turn off the rear height control air
suspension. Otherwise, the vehicle height may be
changed in the automatic leveling function, resulting in
accident. For details, see Rear height control air
suspensionº on page 395.