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5137-3. Do-it-yourself maintenance
7
Maintenance and care
NX300h_U_OM78007U Make sure that the 12-volt battery terminals are not corroded and that there are
no loose connections, cracks, or loose clamps.
Te r m i n a l s
Hold-down clamp
Insert the left side auxiliary box.
Push up center position
Insert
Press ■
Before recharging
When recharging, the 12-volt battery produces hydrogen gas which is flammable and
explosive. Therefore, observe the following precautions before recharging: ●
If recharging with the 12-volt 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 disconnecting
the charger cables to the 12-volt battery. ■
After recharging/reconnecting the 12-volt battery ●
The hybrid system may not start. Follow the procedure below to initialize the system.
Shift the shift lever to P.
Open and close any of the doors.
Restart the hybrid system.●
Unlocking the doors using the smart access system with push-button start may not be
possible immediately after reconnecting the 12-volt battery. If this happens, use the
wireless remote control or the mech anical key to lock/unlock the doors.●
Start the hybrid system with the power switch in ACCESSORY mode. The hybrid sys-
tem may not start with the power switch turned off. However, the hybrid system will
operate normally from the second attempt.Exterior 1
2
Installing the 12-volt battery maintenance cover 1
2
3
1
2
3
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514 7-3. Do-it-yourself maintenance
NX300h_U_OM78007U ●
The power switch mode is recorded by the vehicle. If the 12-volt battery is reconnected,
the vehicle will return the power switch mode to the status it was in before the 12-volt
battery was disconnected. Make sure to turn off the power before disconnect the 12-
volt battery. Take extra care when connecting the 12-volt battery if the power switch
mode prior to discharge is unknown.
If the system will not start even after multiple attempts at all methods above, contact your
Lexus dealer.
WA R N I N G ■
Chemicals in the 12-volt battery
The 12-volt battery contains 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 the 12-volt battery: ●
Do not cause sparks by touching the 12-volt battery terminals with tools. ●
Do not smoke or light a match near the 12-volt battery. ●
Avoid contact with eyes, skin and clothes. ●
Never inhale or swallow electrolyte. ●
Wear protective safety glasses when working near the 12-volt battery.●
Keep children away from the 12-volt battery. ■
Where to safely charge the 12-volt battery
Always charge the 12-volt battery in an open area. Do not charge the 12-volt battery in
a garage or closed room where th ere is insufficient ventilation.■
How to recharge the 12-volt battery
Only perform a slow charge (5 A or less). The 12-volt battery may explode if charged
at a quicker rate. ■
Emergency measures regarding electrolyte ●
If electrolyte gets in your eyes
Flush your eyes with clean water for at least 15 minutes and get immediate medical
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 fe el pain or burning, get medical attention
immediately. ●
If electrolyte gets on your clothes
It can soak through clothing on to your skin. Immediately take off the clothing and fol-
low the procedure above if necessary. ●
If you accidentally swallow electrolyte
Drink a large quantity of water or milk. Get emergency medica l attention immedi-
ately.
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5157-3. Do-it-yourself maintenance
7
Maintenance and care
NX300h_U_OM78007U WA R N I N G ■
When handling the 12-volt battery
P. 5 9 9 ■
When disconnecting the 12-volt battery
NOTICE ■
When recharging the 12-volt battery
Never recharge the 12-volt battery while the hybrid system is operating. Also, be sure
all accessories are turned off.Do not disconnect the negative (-) terminal on
the body side as shown. The disconnected neg-
ative (-) terminal may to uch the positive (+) ter-
minal, which may cause a short and result in
death or serious injury.
Page 516 of 681
516 7-3. Do-it-yourself maintenance
NX300h_U_OM78007UTires New tread
Treadwear indicator
Wo r n t r e a d The location of treadwear indicators is
shown by the “TWI” or “ ” marks, etc.,
molded on the sidewall of each tire.
Check spare tire condition and pressure
if not rotated.
Rotate the tires in the order shown. To equalize tire wear and help extend tire life, Lexus recommends that you rotate your
tires approximately at the following intervals:
2WD models:
Every 6000 miles (10000 km)
AW D m o d e l s :
Every 3000 miles (5000 km)
Do not fail to initialize the tire pressu re warning system after tire rotation.Replace or rotate tires in accordance with maintenance schedules and tread-
wear.
Checking tires 1
2
3
Tire rotation
Vehicles with compact spare tire
Vehicles with full-size spare tire
Front Front
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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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518 7-3. Do-it-yourself maintenance
NX300h_U_OM78007U ■
How to initialize the tire pressure warning system
Park the vehicle in a safe place and turn the power switch off. Initialization cannot be performe d while the vehicle is moving.
Adjust the tire inflation pressure to the specified cold tire inflation pressure
level. ( P. 6 1 5 )Make sure to adjust the tire pressure to the specified cold tire inflation pressure
level. The tire pressure warning system w ill operate based on this pressure level.
Turn the power switch to ON mode.
Press of the meter con-
trol switch.
Press or of the meter con-
trol switch, select , and
then press .
Press or of the meter con-
trol switch, select the “TPMS”
screen and then press and hold
the . 1
2
3
4
5
6
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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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520 7-3. Do-it-yourself maintenance
NX300h_U_OM78007U ■
Maximum load of tire
Check that the maximum load of the replacem ent 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.
■
Tire types ●
Summer tires
Summer tires are high-speed performance tires best suited to highway driving under
dry conditions. Since summer tires do not have the same traction performance as
snow tires, summer tires are inadequate for driving on snow-covered or icy roads. For
driving on snow-covered roads or icy roads, the use of snow tires is recommended.
When installing snow tires, be sure to replace all four tires. ●
All season tires
All season tires are designed to provide better traction in snow and to be adequate for
driving in most winter condit ions as well as for use year-round. All season tires, how-
ever, do not have adequate traction performance compared with snow tires in heavy
or loose snow. Also, all season tires fall short in acceleration and handling perfor-
mance compared with summer tires in highway driving. ●
Snow tires
For driving on snow-covered roads or icy roads, we recommend using snow tires. If
you need snow tires, select tires of the same size, construction and load capacity as the
originally installed tires. Since your vehicle has radial tires as original equipment, make
sure your snow tires also have radial cons truction. Do not install studded tires without
first checking local regulations for possible re strictions. Snow tires should be installed
on all wheels. ( P. 3 2 6 )■
Initializing the tire pressure warning system
Initialize the system with the tire inflation pressure adjusted to the specified level. ■
If the tread on snow tires wears down below 0.16 in. (4 mm)
The effectiveness of the tires as snow tires is lost.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. 6 2 1 )