2003 Lexus GX470 check engine light

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GAUGES, METERS AND SERVICE REMINDER INDICATORS
44IF THIS INDICATOR OR
BUZZER COMES ON ...
DO THIS.
(k)Stop and check.
(l)Stop and check.
(m)Replace engine oil.
(n)Fill up tank.
(o)Add washer fluid.
(p)Key reminder buzzerRemove key.
(a) Brake System Warning Light and Buzzer
This light comes on in the following cases when the ignition key
is in the “ON” position.
 When the parking brake is applied ...
This light comes on for a few seconds when the ignition key is
in the “ON” position even after the parking brake is released.
 When the brake fluid level is low ...
CAUTION
It is dangerous to continue driving normally when the
brake fluid level is low.
When the hydraulic brake booster fails ...
If the hydraulic booster causes a problem resulting in poor
braking performance, the warning light comes on and buzzer
sounds continuously.
Have your vehicle checked at your Lexus dealer in the
following cases:
 The light does not come on even if the parking brake is
applied when the ignition key is in the “ON” position.
 The light does not come on even if the ignition key is turned
on with the parking brake released.
A warning light turning on briefly during operation does not
indicate a problem.

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GAUGES, METERS AND SERVICE REMINDER INDICATORS
47
(e) Malfunction Indicator Lamp
This lamp comes on when the ignition key is turned to the
“ON” position and goes off after the engine starts. This
means that the warning light system is operating properly.
If the lamp remains on, or the lamp comes on while driving,
first check the followings.
 Empty fuel tank
If the fuel tank is empty, refuel immediately.
 Loose fuel tank cap
If the fuel tank cap is loose, securely tighten it.
These cases are temporary malfunctions. The malfunction
indicator lamp will go off after taking several driving trips.
If the lamp will not go off even after the several trips, contact
your Lexus dealer as soon as possible.
If the fuel tank is not empty or the fuel tank cap is not
loose ...
 There is a problem somewhere in the engine, emission
control system, electronic throttle control system, automatic
transmission electrical system or warning light system itself.
Contact your Lexus dealer as soon as possible to service the
vehicle.
If the engine speed does not increase with the accelerator
pedal depressed down, there may be a problem somewhere
in your electronic throttle control system. At this time, vibration may occur. However, if you depress the
accelerator pedal more firmly and slowly, you can drive your
vehicle at low speeds. Have your vehicle checked by your
Lexus dealer as soon as possible.
Even if the abnormality of the electronic throttle control system
is corrected during low speed driving, the system may not be
recovered until the engine is stopped and the ignition key is
turned to “ACC” or “LOCK” position.
CAUTION
Be especially careful to prevent erroneous pedal
operation.
Emissions inspection and maintenance (I/M) programs
Your vehicle may not pass a state emission inspection if the
malfunction indicator lamp remains on. Contact your Lexus
dealer to check your vehicle’s emission control system and
OBD (On−Board Diagnostics) system before taking your
vehicle for the inspection.
For details, see “Emissions inspection and maintenance (I/M)
programs” on page 401.

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GAUGES, METERS AND SERVICE REMINDER INDICATORS
50
(j) “VSC TRAC” Warning Light
The light warns that there is a problem somewhere in the
following.
Vehicle skid control system
 Active traction control system
 Downhill assist control system
 Hill− start assist control system
The light will come on when the ignition key turned to “ON”, and
will go off after a few seconds.
It is not a malfunction that the warning light may stay on for 60
seconds after the ignition key is turned to the “ON” position.
Depressing the brake pedal repeatedly may turn on the lights.
It is normal if they go out after a few seconds.
There is no problem when the “VSC TRAC” warning light
comes on when the brake actuator temperature becomes high.
If the light comes on while driving, the above mentioned
systems do not work. However, as conventional braking
operates when applied, there is no problem to continue your
driving.
In the following cases, contact your Lexus dealer:
 The warning light does not come on after the ignition key is
turned to “ON”.
 The warning light remains on after the ignition key is turned
to “ON”.
 The warning light comes on while driving.
(k) Discharge Warning Light
This light warns that the battery is being discharged.
If it comes on while you are driving, stop the vehicle, turn off the
engine, and check for the cause. Look first at the engine drive
belt.
 If it is loose or broken, the generator will not charge the
battery properly.
 If the belt is O.K., there is a problem somewhere in the
charging system.
The engine ignition will continue to operate, however, until the
battery is discharged. Turn off the air conditioning, blower,
radio, etc., and drive directly to the nearest Lexus dealer or
repair shop.
NOTICE
Do not continue driving if the engine drive belt is broken
or loose.
(l) Low Engine Oil Pressure Warning Light
This light warns that the engine oil pressure is too low.
If it flickers or stays on while you are driving, pull off the road
to a safe place and stop the engine immediately. Call a Lexus
dealer or qualified repair shop for assistance.

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GAUGES, METERS AND SERVICE REMINDER INDICATORS
51
The light may occasionally flicker when the engine is idling or
it may come on briefly after a hard stop. There is no cause for
concern if it then goes out when the engine is accelerated
slightly.
The light may come on when the oil level is extremely low. It
is not designed to indicate low oil level, and the oil level must
be checked using the oil level dipstick.
NOTICE
Do not drive the vehicle with the warning light on even
for one block. It may ruin the engine.
(m) Engine Oil Replacement Reminder Light
This light reminds you when to replace the engine oil.
This light will come on when the ignition key is turned to “ON”
and will go off after about a few seconds.
When you drive for about 8000 km (5000 miles) after the
engine oil replacement, this light illuminates for about 3
seconds and then flashes for about 12 seconds with the
ignition key turned to “ON” position. If you continue driving
without the engine oil replacement, and if the driving range
exceeds
12000 km (7500 miles), the light will come on after the
ignition key is turned to “ON” position. The light will remain on
thereafter.
If the light is flashing, we recommend that you replace the
engine oil at an early opportunity depending on the driving and
road condition. If the light comes on, replace it as soon as
possible. You need to reset the light after the engine oil replacement.
Reset the light by following the procedure below:
1. Turn the ignition key to the “OFF” position with the odometer
reading
shown. (For details, see “Odometer and trip meter” on
page 42.)
2. Turn the ignition key to the “ON” position while holding down
the trip meter reset knob.
Hold down the knob until the light goes off. Before the light
goes off, it illuminates for 3 seconds, flashes for 2 seconds and
illuminates for 1 second.
If the system fails to reset, the light will remain flashing. In this
case, return to step 1 and try again.
(n) Low Fuel Level Warning Light
This light comes on when the fuel level in the tank becomes
very low. Fill the tank as soon as possible.
On inclines or curves, due to the movement of fuel in the tank,
the low fuel level warning light may come on earlier than usual.
(o) Low Washer Fluid Warning Light
This light comes on when the fluid level in the tank becomes
very low. Fill the tank as soon as possible.
(p) Key Reminder Buzzer
This buzzer reminds you to remove the key when you open the
driver’s door with the ignition key in the “ACC” or “LOCK”
position.

STARTING AND DRIVING
302
HOW TO START THE ENGINE
Cranking hold function
Once you turn the ignition key to “START” position and release
it, the cranking hold function continues to crank the engine in
“ON” position until it starts.
The function stops cranking the engine after about 25 seconds
maximum if the engine has not started yet. When you crank
the engine again, wait a few seconds and restart it.
If you hold the key in “START” position, the function will keep
cranking for about 30 seconds maximum.
Before cranking
1. Apply the parking brake firmly.
2. Turn off unnecessary lights and accessories.
3. Put the selector lever in “P”. If you need to restart the engine
while the vehicle is moving, put the selector lever in “N”. A
starter safety device will prevent the starter from operating if
the selector lever is in any drive position.
4. Depress the brake pedal and hold it to the floor until driving
off.
Starting the engine
Before starting the engine, be sure to follow the instructions in
“Before cranking”.
Normal starting procedure
The multiport fuel injection system/sequential multiport fuel
injection system in your engine automatically controls the
proper air −fuel mixture for starting. You can start a cold or hot
engine as follows:
1. With your foot off the acce lerator pedal, turn the ignition key
to “START” position, then release it.
2. After the engine runs for about 10 seconds, you are ready
to drive.
If the weather is below freezing, let the engine warm up for a
few minutes before driving. Do not leave the vehicle while the
engine is warming up.
If the engine stalls ...
Simply restart it , using the correct procedure given in normal
starting.
If the engine will not start ...
See “If your vehicle will not start” on page 359.
NOTICE
 Do not race a cold engine.
 If the engine becomes difficult to start or stalls
frequently, have the engine checked immediately.

STARTING AND DRIVING
317
The height control indicator light indicates which mode is
selected. (See “(e) Height control indicator light” described
below.)

Selecting the “HI” mode
Push the height select switch on the “ ” side when the vehicle
speed is under about 30 km/h (19 mph).
To change the “N” mode to “HI”: Push the switch once.
To change the “LO” mode to “HI”: Push the switch twice.
It takes about 30 seconds until the “LO” mode changes to the
“HI” mode.
 Selecting the “N” mode
To change the “HI” mode to “N”: Push the height select
switch on the “
” side once.
To change the “LO” mode to “N”: Push the height select
switch on the “ ” side once.
 Selecting the “LO” mode
Push the height select switch on the “
” side while the vehicle
is stopped.
To change the “N” mode to “LO”: Push the switch once.
To change the “HI” mode to “LO”: Push the switch twice.
Even if the engine is stopped while the vehicle height is being
lowered, the operation continues for up to 25 seconds. If within
this 25 seconds, any of the side doors or the back door is
opened, operation will continue for a further 15 seconds.
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 “LO” mode in the bumpy roads. If
the underbody of the vehicle touches the rugged
road surface, the vehicle may be damaged.

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(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 “N” mode is automatically selected. If this
occurs, the height control “OFF” 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.
1 For driving on a bumpy road
2 For ordinary driving such as in the city traffic
3 For moderate high speed driving
4 For sporty type driving such as on winding mountain
roads and high speed driving
5 Soft
6 Firm
We recommend you to select the mode
2
for ordinary
driving. The damping effect will be changed automatically to
provide good riding comfort.

STARTING AND DRIVING
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 Slip indicator light
Leave the system on during the ordinary driving so that it
can operate when needed.
You may hear a sound in the engine compartment for a few
seconds when the engine is started or just after the vehicle
begins to move. This means that the active traction control
system is in the self−check mode, but does not indicate a
malfunction.
When the active traction control system is operating, the
following conditions occur:
 The system controls the spinning of the 4 wheels. At this
time, the slip indicator light blinks.
 You may feel vibration or noise in your vehicle, caused by
operation of the brakes. This indicates the system is
functioning properly. The slip indicator light comes on for a few seconds when the
ignition key is turned to “ON”. If the indicator light does not
come on when the ignition is turned on, contact your Lexus
dealer.
“VSC TRAC” warning light
This light warns that there is a problem somewhere in the
following.

Active traction control system
 Vehicle skid control system
 Downhill assist control system
 Hill− start assist control system
When the system is normal and the ignition key is turned to
“ON”, the warning light will come on and will go off after a few
seconds. It is not a malfunction that the warning light may stay
on for 60 seconds after the ignition key is turned to the “ON”
position.