2006 LEXUS LS430 check engine

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4-3. Do-it-yourself maintenance
4
Maintenance and care
Cartridge fuses
■If there is an overload in the circuits from the battery
The fuses are designed to blow before the wiring harness is damaged.
If the headlights or other electrical components do not work and the blade
fuses are O.K., check the cartridge fuses.
■ Fuse location
■ Checking whether fuses ar
e good or blown
Good
Blown
If replacement is necessary,
replace with a genuine Lexus fuse
or equivalent with the same amper -
age rating as original.
Engine CompartmentEngine Compartment
1
2

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5-1. Essential information
If you think something is wrong
If you notice any of the following symptoms, your vehicle probably needs
adjustment or repair. Contact your Lexus dealer as soon as possible.
■Visible symptoms
Look for any of the following symptoms.
• Fluid leaks under the vehicle
Water dripping from the air conditioning after use is normal
• Flat-looking tires or uneven tire wear
• Engine coolant temperature gauge needle continually points higher
than normal
■ A
udible symptoms
Listen for any of the following symptoms.
• Change in exhaust sound
• Excessive tire squeal when cornering
• Strange noises related to suspension system
• Pinging or other noises related to engine
■ P
roblems with operation
Check for any of the following symptoms.
• Engine missing, stumbling or running rough
• Appreciable loss of power
• Vehicle pulls to heavily one side when braking
• Vehicle pulls to heavily one sid e when driving on a le
vel road
• Loss of brake effectiveness, sp ongy feeling, pedal almost touches
floor

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When trouble arises
333
5-2. Steps to take in an emergency
■If the electronic engine control system warning light remains on while driving
First check the following:
• Check fuel level, if the fuel tank is empty, refuel immediately.
• Check the fuel tank cap is loose tighten it securely.
The light will go off after driving regularly for some time.
If the light does not go off even after several trips, contact your Lexus dealer as soon
a
s possible.
■Front passenger detection sensor an d passenger’s seat belt reminder
●If luggage is placed on the front passenger seat, the front passenger detection
sensor may cause the warning light to flash and a chime to sound, even if a pas -
senger is not sitting in the seat.
●If a cushion is placed on the seat, the sensor may not detect a passenger, and the
warning light may not operate properly.
CAUTION
■If both the ABS and brake system warning lights remain on
Stop your vehicle in a safe place immediately and contact your Lexus dealer. The
v

ehicle will become extremely unstable during braking, and the ABS system may
fail, which could cause an accident resulting in death or serious injury.

334
5-2. Steps to take in an emergency
If a warning message appears...
Stop the vehicle immediately.
The following warning indicates the possibility of damage to the vehicle
that may lead to an ac cident. Immediately stop the vehicle in a safe place
and contact your Lexus dealer.
Warning message and lightDetails
Engine oil pressure warning
Indicates abnormal oil pressure.
This warning message may appear it the level of
engine
oil is low. The message should disappear
after checking the oil and adding oil.
If a warning message appears on the multi-information display, check to see
what the problem is and take appropriat e measures referring to the following
table.
Master warning light
Comes on or flashes when a warn -
ing message appears on the multi
information display
. (The warning
light may not come on or flash,
depending on the system. In this
case only the message will be dis -
played.)
Multi information display
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2

5
When trouble arises
337
5-2. Steps to take in an emergency
Have the malfunction repaired immediately.
After taking the specified steps to correct the suspected problem, check
that the warning message disappears.
Warning message and lightDetailsCorrection procedures
(flashes)
Engine oil level warn-
ing
The engine oil level is
low.Check the level of engine
oil and add if necessary.
Open door warning
(Warning buzzer)*1
Check that all doors are
closed.Indicates that a door
is not fully closed.
Graphic information
also appears to let
you know which
door is open.

Open trunk-lid warn-
ing
(Warning buzzer)*1
Indicates that the
trunk-lid is not fully
closed.Check that the trunk-lid
is closed.

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5-2. Steps to take in an emergency
CAUTION
■Using the tire jack
Improper use of the tire jack may lead to death or injuries due to the vehicle sud-
denly falling off the jack. 
Observe the following precautions to prevent accidents.
• Do not use the tire jack for any purpose other than replacing tires or installing and
removing tire chains.
• Only use the tire jack that comes with this vehicle for replacing a flat tire. 
Do not use this tire jack on other vehicl
es, and do not use other tire jacks for
replacing tires on this vehicle.
• Always check that the tire jack is securely set to the jack point.
• Do not raise the vehicle while someone is in it.
• When raising the vehicle, do not put an object on or under the jack.
• Do not raise the vehicle to a height greate r than
that required to replace the tire.
• Do not put any part of your body under the vehicle supported by a jack.
• Do not start or run the engine while your vehicle is supported by the jack.
• Use a jack stand if it is necessary to get under the vehicle.
• Take particular care when lowering the vehicle to ensure that no one working on or
near the vehicle may be injured.
■Replacing a flat tire
Observe the following precautions to reduce
the risk of death or serious injury.
• Never use oil or grease on the wheel bolts or wheel nuts. 
The oil or grease can cause the wheel nuts to loosen, causing a serious accident.
R
emove any oil or grease on the wheel bolts or wheel nuts.
• Have the wheel nuts tightene d with a tor
que wrench to 76 f t•lbf (105 N•m, 10.5
kgf
•m) as soon as possible after changing wheels. 
Failure to follow these pre-cautions could cause, the wheel nuts to loosen and the
w
heels may fall off, which could lead to an accident causing death or serious injury.
NOTICE
■Do not drive the vehicle with a flat tire.
Do not continue driving with a flat tire. 
Driving even a short distance can damage a tire and wheel beyond repair.

5
When trouble arises
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5-2. Steps to take in an emergency
■Avoiding a discharged battery
●Turn off the headlights and the audio system while the engine is turned off.
●Turn off any unnecessary electrical comp onents when the vehicle runs at a low
speed for an extended period, such as in heavy traffic, etc.
CAUTION
■Avoiding battery fires or explosions
Observe the following precautions to prevent accidentally igniting the flammable
ga

s that may be emitted from the battery.
• Make sure the jumper cable is connected to
the correct terminal and that it is
not unintentionally in contact with any part other than the intended terminal.
• Do not allow the booster cables to come into cont
act with the + and - terminals.
• Do not generate a flame near the battery b
y using a match, cigarette lighter, or
smoking.
■Battery precautions
The battery contains poisonous and corrosive electrolyte, while related parts con -
tain lead and lead compounds. 
Observe the following precautions when handling the battery.
• Do not lean over the battery
• When working with the battery, always we ar safety glas
ses and take care not to
allow any battery fluids (acid) to come into contact with skin, clothing or the
vehicle body.
• In the event that battery fluid comes into co
ntact with the skin or eyes, immedi-
ately wash the affected area with water and seek medical attention. Place a wet
sp
onge or cloth over the affected area until medical attention can be received.
• Always wash your hands after ha
ndling battery-related parts.
• Do not allow children near the battery.
Once the engine starts, have the vehicle checked at your Lexus dealer as
soon as possible.

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When trouble arises
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5-2. Steps to take in an emergency
If your vehicle overheats
If your engine overheats
Stop the vehicle in a safe place and turn off the automatic climate
control.
Check to see if steam is coming out from under the hood.
If you see steam: 
Stop the engine.
If you do not see steam: 
Leave the engine running and carefully lift the hood.
Check to see if the cooling fan is operating.
If the fan is operating: 
Wait until the temperature of the engine (shown in the instrument clus -
ter) begins to fall and then stop the engine.
If the fan is not operating: 
Stop the engine and call your local Lexus dealer.
After the engine has cooled down
sufficiently, check the level of
engine coolant and inspect the
radiator core (radiator) for any
leaks.