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5177-3. Do-it-yourself maintenance
7
Maintenance and care
NX300h_U_OM78007U Your vehicle 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 predet ermined level, the driver is warned by
a warning light. ( P. 5 6 7 )
◆ 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 initialized. Have tire pressure warning valve
and transmitter ID codes registered by your Lexus dealer. ( P. 5 1 9 )
◆ Initializing the tire pressure warning system ■
The tire pressure warning system must be initialized in the following circum-
stances: ●
When changing the tire inflation pressure ●
When the tire inflation pressure is changed such as when changing travel-
ing speed or load weight. ●
When rotating the tires ●
When changing the tire.
When the tire pressure warning system is initialized, the current tire inflation
pressure is set as the benchmark pressure.Tire pressure warning system ●
The tire pressure detected by the tire
pressure warning system can be dis-
played on the multi-information display.
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5197-3. Do-it-yourself maintenance
7
Maintenance and care
NX300h_U_OM78007U A message and an indicator are
displayed by the multi-informa-
tion display, and initialization is
completed.
◆ Registering ID codes
The tire pressure warning valve and transmitter 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. ■
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 prop erly 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 proper ly. After driving for about 20 minutes, the
tire pressure warning light blinks for 1 minute 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.7
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5217-3. Do-it-yourself maintenance
7
Maintenance and care
NX300h_U_OM78007U ■
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 wheel without the tire pressure warning valve and transmitter is 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 th at generates strong radio waves or electrical noise
• When carrying a portable radio, cellular phone, cordless ph one 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. ■
The initialization operation ●
Make sure to carry out initialization af ter adjusting the tire inflation pressure.
Also, make sure the tires are cold before carry ing out initialization or tire inflation pres-
sure adjustment. ●
If you have accidentally turned the power swit ch off during initializat ion, it is not neces-
sary to press the reset switch again as init ialization will restart automatically when the
power switch has been turned to ON mode for the next time. ●
If you accidentally press the reset switch when initialization is not necessary, adjust the
tire inflation pressure to the specified leve l when the tires are co ld, and conduct initial-
ization again. ■
Warning performance of the tire pressure warning system
The warning of the tire pressure warning syst em will change in accordance with the con-
ditions under which it was initialized. For this reason, the system may give a warning even
if the tire pressure does not reach a low enough level, or if the pressure is higher than the
pressure that was adjusted to when the system was initialized. ■
When initialization of the tire pressure warning system has failed
Initialization can be completed in a few minutes. However, in the following cases, the set-
tings have not been recorded and the system will not operate properly. If repeated
attempts to record tire inflation pressure settings are unsuccessful, have the vehicle
inspected by your Lexus dealer. ●
When operating the tire pressure warning reset switch, the tire pressure warning light
does not blink 3 times. ●
After carrying out the initializ ation procedure, the tire pres sure warning light blinks for
1 minute then stays on after driving for 20 minutes.
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Maintenance and care
NX300h_U_OM78007U WA R N I N G ■
When inspecting or replacing tires
Observe the following precautions to prevent accidents.
Failure to do so may cause damage to parts of the drive train as well as dangerous han-
dling characteristics, which may lead to an accident resultin g in death or serious injury.●
Do not mix tires of different makes, models or tread patterns.
Also, do not mix tires of remarkably different treadwear. ●
Do not use tire sizes other than those recommended by Lexus. ●
Do not mix differently constructed tires (radial, bias-belted or bias-ply tires). ●
Do not mix summer, all season and snow tires. ●
Do not use tires that have been used on another vehicle.
Do not use tires if you do not know how they were used previously. ●
Vehicles with a compact spare tire: Do no t tow if your vehicle has a compact spare
tire installed. ■
When initializing the tire pressure warning system
Do not initializing tire inflation pressure wi thout first adjusting the tire inflation pressure
to the specified level. Otherwise, the tire pressure warning light may not come on even
if the tire inflation pressure is low, or it may come on when the tire inflation pressure is
actually normal. ■
Caution regarding interference with electronic devices
●
Users of any electrical medical device other than implantable cardiac pacemakers,
cardiac resynchronization therapy-pacemakers or implantable cardioverter defibril-
lators should consult the ma nufacturer of the device for information about its opera-
tion under the influence of radio waves.
Radio waves could have unexpected effe cts on the operation of such medical
devices. ●
People with implantable cardiac pacemakers,
cardiac resynchronization therapypacemak-
ers or implantable cardioverter defibrillators
should not come within 17.7 in. (450 mm) of
the tire pressure warning system initiators.
The radio waves may affect the operation of
such devices.
Page 536 of 681
536 7-3. Do-it-yourself maintenance
NX300h_U_OM78007U Check if the fuse is blown.
Normal fuse
Blown fuse Replace the blown fuse with a new fuse of an appropriate amperage rating. The
amperage rating can be found on the fuse box lid.
■
After a fuse is replaced ●
If the lights do not turn on even after the fuse has been replaced, a bulb may need
replacement. ( P. 5 3 8 )●
If the replaced fuse blows again, have the vehicle inspected by your Lexus dealer. ■
If there is an overload in a circuit
The fuses are designed to blow, protec ting the wiring harness from damage.■
When replacing light bulbs
Lexus recommends that you use genuine Lexu s products designed for this vehicle.
Because certain bulbs are connected to circui ts designed to prevent overload, nongenu-
ine parts or parts not designed for this vehicle may be unusable. 4
1
2
Ty p e A
Ty p e B
Ty p e C
Ty p e D
Page 538 of 681
538 7-3. Do-it-yourself maintenance
NX300h_U_OM78007ULight bulbs Check the wattage of the light bulb to be replaced. ( P. 6 1 7 )
P. 5 0 3
P. 1 3 2You may replace the following bulbs by yourself. The difficulty level of replace-
ment varies depending on the bulb. If necessary bulb replacement seems diffi-
cult to perform, contact your Lexus dealer.
For more information about replacing other light bulbs, contact your Lexus
dealer.
Preparing for light bulb replacement
Removing the engine compartment cover
Canceling the power back door system
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5397-3. Do-it-yourself maintenance
7
Maintenance and care
NX300h_U_OM78007U ■
Front
Bulb locations
Front turn signal light (bulb type)
Headlight high beam (halogen
bulbs) Front side marker light (bulb type)1
2 3
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540 7-3. Do-it-yourself maintenance
NX300h_U_OM78007U ■
Rear
Back-up light
Rear turn signal light 1
2