2003 TOYOTA 4RUNNER check engine

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If the light comes on while driving, the
active traction control system does not
work. However, as normal braking oper-
ates when being applied, there is no prob-
lem to continue your driving.
In the following cases, contact your Toyota
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 driv-
ing. The vehicle stability control system
helps provide integrated control of the
systems such as antilock brake sys-
tem, traction control, engine control,
etc. This system automatically controls
the output of the brakes or engine to
help prevent the vehicle from skidding
when cornering on a slippery road sur-
face or operating steering wheel abrupt-
ly.
The vehicle stability control activates
when the vehicle speed is more than 15
km/h (9 mph).
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 sys-
tem is in the selfcheck mode, but does
not indicate a malfunction.
CAUTION
Do not rely excessively on the ve-
hicle stability control system. Even
if the vehicle stability control sys-
tem is operating, you must always
drive carefully and attentively to
avoid serious injury. Reckless driv-
ing will result in an unexpected ac-
cident. If the slip indicator light
blinks and an alarm sounds, special
care should be taken while driving.
Only use tires of specified size. The
size, manufacturer, brand and tread
pattern for all 4 tires should be the
same. If you use the tires other
than specified, or different type or
size, the vehicle stability control
system may not function correctly.
When replacing the tires or wheels,
contact your Toyota dealer. (See
“Checking and replacing tires” on
page 333 in Section 72.)
Vehicle stability control
system

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To change the “LO” mode to “HI”, push
the switch twice. It takes about 30 sec-
onds 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 ve-
hicle 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 fre-
quently when the vehicle is heavily
loaded, the compressor may over-
heat, causing the vehicle height ad-
justment 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 ve-
hicle equipped with the rear height
control air suspension becomes
slightly higher than the normal ve-
hicle height. Take sufficient care
where the overhead height is re-
stricted.
 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 dam-
aged.

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(e) Height control indicator lights
1. Height control indicator lights
2. Height control “OFF” indicator light
When the ignition switch is turned on, all the
indicator lights come on. The indicator light
showing the present mode only remains on
and all other lights go off after a few sec-
onds. This means the system operates correct-
ly.If you change the vehicle height mode,
the indicator lights change as follows:
When changing the vehicle height from
the “N” mode to “HI”:
1. The “N” mode indicator light goes off and the “HI” mode indicator light blinks.
2. After the vehicle height control reaches the “HI” mode, the “HI” 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 vehicle height cannot
be lowered with the height select switch.
The height control 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.
In this case, even if the vehicle is moved
to its usual location or the ice is removed
and the height select switch is pressed,
vehicle height control cannot be operated.
Turn off the engine once and then restart
it.
Height control “OFF” 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 sus-
pension operates correctly. If you push the
“HEIGHT CONTROL OFF” switch, the rear
height control air suspension is turned off.
The height control “OFF” 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 Toyota dealer as soon as possible.

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The height control “OFF” indicator light
does not come on when the ignition
switch is turned on.
The height control “OFF” indicator light
blinks.
(f) Parking and stopping tips
If you immediately stop the engine to park
the vehicle after offroad driving, the ve-
hicle height is lowered slightly as the ve-
hicle becomes cool. When parking, make
sure there is nothing that will be in con-
tact 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 low-
ered. When parking for a long time, make
sure there is nothing that will be in con-
tact 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 oc-
curs, 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 Toyota dealer as soon as
possible and have it checked.
When parking, firmly apply the parking
brake to avoid inadvertent creeping.
To set: Fully depress the parking brake
pedal. For better holding power, first de-
press the brake pedal and hold it while
setting the parking brake.
To release: Depress the parking brake
pedal once again.
To remind you that the parking brake is
set, the parking brake reminder light in
the instrument panel remains on until you
release the parking brake.
Parking brake

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SETTING AT A DESIRED SPEED
The transmission must be in “D” before
you set the cruise control speed.
Bring your vehicle to the desired speed,
push the lever down in the “ SET” direc-
tion and release it. This sets the vehicle
at that speed. If the speed is not satisfac-
tory, tap the lever up for a faster speed,
or tap it down for a slower speed. Each
tap changes the set speed by 1.6 km/h
(1.0 mph). You can now take your foot off
the accelerator pedal. If you need acceleration—for example,
when passing—depress the accelerator
pedal enough for the vehicle to exceed
the set speed. When you release it, the
vehicle will return to the speed set prior
to the acceleration.
CANCELLING THE PRESET SPEED
You can cancel the preset speed by:
a. Pulling the lever in the “CANCEL” di-
rection and releasing it.
b. Depressing the brake pedal.
If the vehicle speed falls below about 40
km/h (25 mph), the preset speed will auto-
matically cancel out.
If the vehicle speed drops 16 km/h (10
mph) below the preset speed, the preset
speed will also automatically cancel out.
If the preset speed automatically cancels
out other than for the above cases, have
your vehicle checked by your Toyota deal-
er at the earliest opportunity. RESETTING TO A FASTER SPEED
Push the lever up in the “+ RES” direction
and hold it. Release the lever when the
desired speed is attained. While the lever
is held up, the vehicle will gradually gain
speed.
However, a faster way to reset is to ac-
celerate the vehicle and then push the
lever down in the “ SET” direction.
RESETTING TO A SLOWER SPEED
Push the lever down in the “ SET” direc-
tion and hold it. Release the lever when
the desired speed is attained. While the
lever is held down, the vehicle speed will
gradually decrease.
However, a faster way to reset is to de-
press the brake pedal and then push the
lever down in the “ SET” direction.
Even if you downshift from “D” to “4”
(5speed automatic transmission) or “3”
(4speed automatic transmission), with the
cruise control on, engine braking will not
be enabled because the cruise control is
not cancelled. To decrease the vehicle
speed, reset to a slower speed with the
cruise control lever or depress the brake
pedal. If you use the brake pedal, cruise
control is cancelled.

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Keep your engine in good running
order. Malfunctions in the engine
electrical system, electronic ignition
system/distributor ignition system
or fuel systems could cause an ex-
tremely high threeway catalytic
converter temperature.
 If the engine becomes difficult to
start or stalls frequently, take your
vehicle in for a checkup as soon
as possible. Remember, your Toyota
dealer knows your vehicle and its
threeway catalytic converter sys-
tem best.
 To ensure that the threeway cata-
lytic converter and the entire emis-
sion control system operate proper-
ly, your vehicle must receive the
periodic inspections required by the
Toyota Maintenance Schedule. For
scheduled maintenance information,
refer to the “Scheduled Maintenance
Guide” or “Owner ’s Manual Supple-
ment”.CAUTION
Avoid inhaling the engine exhaust.
It contains carbon monoxide, which
is a colorless and odorless gas. It
can cause unconsciousness or even
death.
Make sure the exhaust system has
no holes or loose connections. The
system should be checked from
time to time. If you hit something,
or notice a change in the sound of
the exhaust, have the system
checked immediately.
Do not run the engine in a garage
or enclosed area except for the
time needed to drive the vehicle in
or out. The exhaust gases cannot
escape, making this a particularly
dangerous situation.
Do not remain for a long time in a
parked vehicle with the engine run-
ning. If it is unavoidable, however,
do so only in an unconfined area
and adjust the heating or cooling
system to force outside air into the
vehicle.
Keep the back door and back win-
dow closed while driving. An open
or unsealed back door and back
window, may cause exhaust gases
to be drawn into the vehicle.
To allow proper operation of your
vehicle’s ventilation system, keep
the inlet grilles in front of the wind-
shield clear of snow, leaves, or oth-
er obstructions.
If you smell exhaust fumes in the
vehicle, drive with the windows
open and the back door and back
window closed. Have the cause im-
mediately located and corrected.
Engine exhaust cautions

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FUNCTIONS OF ENGINE OIL
Engine oil has the primary functions of
lubricating and cooling the inside of the
engine, and plays a major role in main-
taining the engine in proper working order.
ENGINE OIL CONSUMPTION
It is normal that an engine should con-
sume some engine oil during normal
engine operation. The causes of oil
consumption in a normal engine are as
follows.
Oil is used to lubricate pistons, piston
rings and cylinders. A thin film of oil
is left on the cylinder wall when a pis-
ton moves downwards in the cylinder.
High negative pressure generated when
the vehicle is decelerating sucks some
of this oil into the combustion chamber.
This oil as well as some part of the oil
film left on the cylinder wall is burned
by the high temperature combustion
gases during the combustion process.
Oil is also used to lubricate the stems
of the intake valves. Some of this oil
is sucked into the combustion chamber
together with the intake air and is
burned along with the fuel. High tem-
perature exhaust gases also burn the
oil used to lubricate the exhaust valve
stems.
The amount of engine oil consumed de-
pends on the viscosity of the oil, the
quality of the oil and the conditions the
vehicle is driven under.
More oil is consumed by highspeed driv-
ing and frequent acceleration and decel-
eration.
A new engine consumes more oil, since
its pistons, piston rings and cylinder walls
have not become conditioned.
Oil consumption: Max. 1.0 L per 1000
km (1.1 qt./600 miles, 0.9 lmp. qt./600
miles)
When judging the amount of oil con-
sumption, note that the oil may become
diluted and make it difficult to judge
the true level accurately. As an example, if a vehicle is used for
repeated short trips, and consumes a nor-
mal amount of oil, the dipstick may not
show any drop in the oil level at all, even
after 1000 km (600 miles) or more. This
is because the oil is gradually becoming
diluted with fuel or moisture, making it
appear that the oil level has not changed.
The diluting ingredients evaporate out
when the vehicle is then driven at high
speeds, as on an expressway, making it
appear that oil is excessively consumed
after driving at high speeds.
IMPORTANCE OF ENGINE OIL LEVEL
CHECK
One of the most important points in prop-
er vehicle maintenance is to keep the en-
gine oil at the optimum level so that oil
function will not be impaired. Therefore, it
is essential that the oil level be checked
regularly. Toyota recommends that the oil
level be checked every time you refuel
the vehicle.
NOTICE
Failure to check the oil level regularly
could lead to serious engine trouble
due to insufficient oil.
Facts about engine oil
consumption

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For detailed information on oil level check,
see “Checking the engine oil level” on
page 324 in Section 72.
Your engine is fitted with iridiumtipped
spark plugs.
NOTICE
Use only iridiumtipped spark plugs
and do not adjust gaps for your en-
gine performance and smooth drive-
ability.
This brake system has 2 independent hy-
draulic circuits. If either circuit should fail,
the other will still work. However, the ped-
al will be harder to press, and your stop-
ping distance will increase. Also, the
brake system warning light may come on.
CAUTION
Do not drive your vehicle with only a
single brake system. Have your
brakes fixed immediately.
BRAKE BOOSTER
The brake booster uses brake fluid pres-
surized by the pump to powerassist the
brakes. If the brake booster fails during
driving, the brake system warning light
comes on and buzzer sounds continuous-
ly. In this case, the brakes may not work
properly. If they do not work well, depress
the brake pedal firmly. If the brake system
warning light comes on, immediately stop
your vehicle and contact your Toyota deal-
er.
It is not a malfunction that the brake sys-
tem warning light may stay on for 60 sec-
onds after the ignition key is turned to the
“ON” position.
Iridiumtipped spark plugs
(2UZFE engine) Brake system