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GX 460 _O M_ OM6 0L 72U _( U)
4696-3. Do-it-yourself maintenance
6
Maintenance and care
Your Lexus is equipped with a tire pressure warning system that uses tire pres-
sure warning valves and transmitters to detect low tire inflation pressure before
serious problems arise.
If the tire pressure drops below a predetermined level, the driver is warned by a
warning light. ( →P. 5 1 3 )
◆Installing tire pressure warning valves and transmitters
When replacing tires or wheels, tire pressure warning valves and transmitters
must also be installed.
When new tire pressure warning valves and transmitters are installed, new ID
codes must be registered in the tire pressure warning computer and the tire
pressure warning system must be initiali zed. Have tire pressure warning valve
and transmitter ID codes registered by your Lexus dealer.
◆Registering ID codes
The tire pressure warning valve and tr ansmitter is equipped with a unique ID
code. When replacing a tire pressure warning valve and transmitter, it is nec-
essary to register the ID code. Have the ID code registered by your Lexus
dealer.
Tire pressure warning system
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GX 460 _O M_ OM6 0L 72U _( U)6-3. Do-it-yourself maintenance
■When to replace your vehicle’s tires
Tires should be replaced if:
●You have tire damage such as cuts, splits, cracks deep enough to expose the fabric, and
bulges indicating internal damage
●A tire goes flat repeatedly or cannot be properly repaired due to the size or location of
a cut or other damage
If you are not sure, consult with your Lexus dealer.
■Replacing tires and wheels
If the ID code of the tire pressure warning valve and transmitter is not registered, the tire
pressure warning system will not work properly. After driving for about 20 minutes, the
tire pressure warning light blinks for 1 minu te and stays on to indicate a system malfunc-
tion.
■Tire life
Any tire over 6 years old must be checked by a qualified technician even if it has seldom
or never been used or damage is not obvious.
■Routine tire inflation pressure checks
The tire pressure warning system does not replace routine tire inflation pressure checks.
Make sure to check tire inflation pressure as part of your routine of daily vehicle checks.
■Maximum load of tire
Check that the number given by dividing the maximum load by 1.10 of the replacement
tire is greater than 1 /2 of the Gross Axle Weight Ratings (GAWR) of either the front axle
or the rear axle, whichever is greater.
For the GAWR, see the Certification Label. For
the maximum load of the tire, see the load limit
at maximum cold tire inflation pressure men-
tioned on the sidewall of the tire. ( →P. 5 7 5 )
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GX 460 _O M_ OM6 0L 72U _( U)6-3. Do-it-yourself maintenance
■If the tread on snow tires wears down below 0.16 in. (4 mm)
The effectiveness of the tires as snow tires is lost.
■Situations in which the tire pressure warning system may not operate properly
●In the following cases, the tire pressure warning system may not operate properly.
• If non-genuine Lexus wheels are used.
• A tire has been replaced with a tire that is not an OE (Original Equipment) tire.
• A tire has been replaced with a tire that is not of the specified size.
• Tire chains etc. are equipped.
• Lock nuts are equipped.
• An auxiliary-supported run-flat tire is equipped.
• If a window tint that affects the radio wave signals is installed.
• If there is a lot of snow or ice on the vehicle, particularly around the wheels or wheel
housings.
• If the tire inflation pressure is extremely higher than the specified level.
• If the spare tire is in a location subject to poor radio wave signal reception.
• If a large metallic object which can interf ere with signal reception is put near the
spare tire.
• If tires not equipped with the tire pressure warning valves and transmitters are used.
• If the ID code on the tire pressure warning valves and transmitters is not registered in the tire pressure warning computer.
●Performance may be affected in the following situations.
• Near a TV tower, electric power plant, gas station, radio station, large display, air-port or other facility that generates st rong radio waves or electrical noise
• When carrying a portable radio, cellular phone, cordless phone or other wireless communication device
●When the vehicle is parked, the time taken for the warning to start or go off could be
extended.
●When tire inflation pressure declines rapidly for example when a tire has burst, the
warning may not function.
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