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4-2. Maintenance
4
Maintenance and care
GX460_U.S.A. (OM60E69U)
Emission inspection and maintenance (I/M) programs
Some states have vehicle emission inspection programs which include
OBD (On Board Diagnostics) checks. The OBD system monitors the oper-
ation of the emission control system.
■ If the malfunction indicator lamp comes on
The OBD system determines that a problem exists somewhere in
the emission control system. Your vehicle may not pass the I/M test
and may need to be repaired. Contact your Lexus dealer to service
the vehicle.
■ Your vehicle may not pass the I/M test in the following situations:
●When the battery is disconnected or discharged
Readiness codes that are set during ordinary driving are erased.
Also, depending on your driving habits, the readiness codes may
not be completely set.
● When the fuel tank cap is loose
The malfunction indicator lamp comes on a temporary malfunc-
tion and your vehicle may not pass the I/M test.
■ When the malfunction indicator la mp still remains on after several
driving trips
The error code in the OBD system will not be cleared unless the
vehicle is driven 40 or more times.
■ If your vehicle does not pass the I/M test
Contact your Lexus dealer to prep are the vehicle for re-testing.
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GX460_U.S.A. (OM60E69U)
4-3. Do-it-yourself maintenance
Do-it-yourself service precautions
If you perform maintenance yourself, be sure to follow the correct proce-
dure given in these sections.
ItemsPa r t s a n d t o o l s
Battery condition (P. 622)
•Warm water
• Baking soda
•Grease
• Conventional wrench
(for terminal clamp bolts)
Brake fluid level ( P. 6 1 8 )
• FMVSS No.116 DOT 3 or SAE
J1703 brake fluid
•Rag or paper towel
• Funnel (used only for adding brake
fluid)
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4-3. Do-it-yourself maintenance
4
Maintenance and care
GX460_U.S.A. (OM60E69U)
CAUTION
The engine compartment contains many mechanisms and fluids that may move sud-
denly, become hot, or become electrically energized. To avoid death or serious injury,
observe the following precautions:
■When working on the engine compartment
●Keep hands, clothing, and tools away from the moving fan and engine drive belt.
●Be careful not to touch the engine, radiator , exhaust manifold, etc. right after driv-
ing as they may be hot. Oil and other fluids may also be hot.
●Do not leave anything that may burn easily , such as paper or rags, in the engine
compartment.
●Do not smoke, cause sparks or expose an open flame to fuel or the battery. Fuel
and battery fumes are flammable.
●Be extremely cautious when working on the battery. It contains poisonous and
corrosive sulfuric acid.
■When working near the electric cooling fans or radiator grille:
Be sure the “ENGINE START STOP” switch is off.
With the “ENGINE START STOP” switch in IGNITION ON mode, the electric
cooling fans may automatically start to run if the air conditioning is on and/or the
coolant temperature is high. ( P. 6 1 7 )
■Safety glasses
Wear safety glasses to prevent flying or fall ing material, fluid spray, etc. from getting
in your eyes.
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4-3. Do-it-yourself maintenance
GX460_U.S.A. (OM60E69U)
Engine compartment
Engine coolant reservoir
( P. 615)
Engine oil level dipstick
( P. 610)
Engine oil filler cap
( P. 611)
Brake fluid reservoir
( P. 6 1 8 )Fuse box ( P. 645)
Battery ( P. 622)
Radiator ( P. 617)
Condenser ( P. 617)
Electric cooling fan
Washer fluid tank ( P. 6 2 6 )
Power steering fluid reservoir
( P. 6 2 0 )
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4-3. Do-it-yourself maintenance
GX460_U.S.A. (OM60E69U)
BatteryCheck the battery as follows:
■ Battery exterior
Make sure that the battery terminals are not corroded and that there
are no loose connections, cracks, or loose clamps.
Terminals
Hold-down clamp
■ Checking battery condition
Check the battery condition by indicator color.
Blue: Good condition
White: Charging is necessary.
Have the vehicle inspected by
your Lexus dealer.
Red: Not working properly.
Have the battery checked by
your Lexus dealer.
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4-3. Do-it-yourself maintenance
4
Maintenance and care
GX460_U.S.A. (OM60E69U)
■Before recharging
When recharging, the battery produces hydrogen gas which is flammable and
explosive. Therefore, observe the following before recharging:
●If recharging with the battery installed on the vehicle, be sure to disconnect the
ground cable.
●Make sure the power switch on the charger is off when connecting and discon-
necting the charger cables to the battery.
■After recharging/reconnecting the battery
●Unlocking the doors using the smart key system may not be possible immedi-
ately after disconnecting the battery. If this happens, use the wireless remote
control or the mechanical key to lock/unlock the doors.
●Start the engine with the “ENGINE START STOP” switch in ACCESSORY
mode. The engine may not start with the “ENGINE START STOP” switch
turned OFF. However, the engine will operate normally from the second
attempt.
●The “ENGINE START STOP” switch mode is recorded by the vehicle. If the bat-
tery is reconnected, the vehicle will return the “ENGINE START STOP” switch
mode to the status it was in before th e battery was disconnected. Make sure to
turn off the engine before disconnect the battery. Take extra care when con-
necting the battery if the “ENGINE START STOP” switch mode prior to dis-
charge is unknown.
If the system will not start even after mult iple attempts, contact your Lexus dealer.
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4-3. Do-it-yourself maintenance
GX460_U.S.A. (OM60E69U)
CAUTION
■Chemicals in the battery
Batteries contain poisonous and corrosive sulfuric acid and may produce hydrogen
gas which is flammable and explosive. To reduce the risk of death or serious injury,
take the following precautions while working on or near battery:
●Do not cause sparks by touching the battery terminals with tools.
●Do not smoke or light a match near the battery.
●Avoid contact with eyes, skin and clothes.
●Never inhale or swallow electrolyte.
●Wear protective safety glasses when working near the battery.
●Keep children away from the battery.
■Where to safely charge the battery
Always charge the battery in an open area. Do not charge the battery in a garage or
closed room where there is not sufficient ventilation.
■How to recharge the battery
Only perform a slow charge (5A or less). The battery may explode if charged at a
quicker rate.
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4-3. Do-it-yourself maintenance
4
Maintenance and care
GX460_U.S.A. (OM60E69U)
CAUTION
■Emergency measures regarding electrolyte
●If electrolyte gets in your eyes
Flush your eyes with clean water for at least 15 minutes and seek immediate med-
ical attention. If possible, continue to apply water with a sponge or cloth while
traveling to the nearest medical facility.
●If electrolyte gets on your skin
Wash the affected area thoroughly. If you feel pain or a burning sensation, seek
medical attention immediately.
●If electrolyte gets on your clothes
It can soak through clothing on to your skin. Immediately take off the clothing and
follow the procedure above if necessary.
●If you accidentally swallow electrolyte
Drink a large quantity of water or milk. Get emergency medical attention imme-
diately.
NOTICE
■When recharging the battery
Never recharge the battery while the engine is running. Also, be sure all accesso-
ries are turned off.