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4987-3. Do-it-yourself maintenance
NX300h_OM_USA_OM78082U
Do-it-yourself service precautions
If you perform maintenance by yourself, be sure to follow the correct proce-
dure as given in these sections.
ItemsPa r t s a n d t o o l s
12-volt battery con-
dition ( P. 5 1 2 )•Grease
• Conventional wrench (for terminal clamp bolts)
Brake fluid level
( P. 5 1 0 )
• FMVSS No.116 DOT 3 or SAE J1703 brake fluid
• Rag or paper towel
• Funnel (used only for adding brake fluid)
Engine/power con-
trol unit coolant level
( P. 5 0 8 )
• “Toyota Super Long Life Coolant” or a similar high quality
ethylene glycol-based non-silicate, non-amine, non-nitrite
and non-borate coolant with long-life hybrid organic acid
technology
For the U.S.A.:
“Toyota Super Long Life Coolant” is pre-mixed with 50%
coolant and 50% deionized water.
For Canada:
“Toyota Super Long Life Coolant” is pre-mixed with 55%
coolant and 45% deionized water.
• Funnel (used only for adding coolant)
Engine oil level
( P. 5 0 4 )
• “Toyota Genuine Motor Oil” or equivalent
• Rag or paper towel
• Funnel (used only for adding engine oil)
Fuses ( P. 5 3 4 )• Fuse with same amperage rating as original
Light bulbs
( P. 5 3 8 )
• Bulb with same number and wattage rating as original
• Phillips-head screwdriver•Flathead screwdriver
•Wrench
Radiator and con-
denser ( P. 5 0 9 )
Tire inflation pres-
sure ( P. 5 2 5 )• Tire pressure gauge• Compressed air source
Wa s h e r f l u i d
( P. 511)• Water or washer fluid containi ng antifreeze (for winter use)
• Funnel (used only for adding water or washer fluid)
Page 502 of 680
5027-3. Do-it-yourself maintenance
NX300h_OM_USA_OM78082U
Engine compartment
■12-volt battery
P. 5 1 2
Fuse box ( P. 5 3 4 )
Engine coolant reservoir (P. 5 0 8 )
Engine oil filler cap ( P. 505)
Power control unit coolant reservoir ( P. 5 0 8 )
Brake fluid reservoir ( P. 5 1 0 ) Radiator (
P. 5 0 9 )
Condenser ( P. 5 0 9 )
Electric cooling fans
Engine oil level dipstick (P. 5 0 4 )
Wa s h e r f l u i d t a n k ( P. 5 1 1 )1
2
3
4
5
6
7
8
9
10
Page 512 of 680
5127-3. Do-it-yourself maintenance
NX300h_OM_USA_OM78082U
12-volt battery
The 12-volt battery is located in the
left-hand side of luggage compart-
ment. Lift the deck board and attach the hook. ( P. 4 5 2 )
Remove the left side deck board.
Remove the cover after removing
the chip. Press
Pull out
Location
Removing the 12-volt battery maintenance cover
1
2
3
1
2
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5137-3. Do-it-yourself maintenance
7
Maintenance and care
NX300h_OM_USA_OM78082U
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 installe d 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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5147-3. Do-it-yourself maintenance
NX300h_OM_USA_OM78082U
●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 there 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 medical attention immedi-
ately.
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5157-3. Do-it-yourself maintenance
7
Maintenance and care
NX300h_OM_USA_OM78082U
WA R N I N G
■When handling the 12-volt battery
P. 5 9 8
■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.
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5327-3. Do-it-yourself maintenance
NX300h_OM_USA_OM78082U
Electronic key battery
●Flathead screwdriver
●Lithium battery CR2032
Take out the mechanical key.
Remove the cover.
To prevent damage to the key, cover the
tip of the flathead screwdriver with a
tape.
Remove the depleted battery.
Insert a new battery with the “+” termi-
nal facing up.
Replace the battery with a new one if it is depleted.
You will need the following items:
Replacing the battery
1
2
3
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5337-3. Do-it-yourself maintenance
7
Maintenance and care
NX300h_OM_USA_OM78082U
■Use a CR2032 lithium battery
●Batteries can be purchased at your Lexus dealer, local electrical appliance shops or
camera stores.
●Replace only with the same or equivalent type recommended by the manufacturer.
●Dispose of used batteries according to the local laws.
■When the card key battery needs to be replaced (if equipped)
The battery for the card key is available only at Lexus dealers. Your Lexus dealer can
replace the battery for you.
■If the electronic key battery is depleted
The following symptoms may occur:
●The smart access system with push-button start and wireless remote control will not
function properly.
●The operational range will be reduced.
WA R N I N G
■Removed battery and other parts
These parts are small and if swallowed by a child, they can cause choking. Keep away
from children. Failure to do so could result in death or serious injury.
NOTICE
■For normal operation afte r replacing the battery
Observe the following precautions to prevent accidents:
●Always work with dry hands.
Moisture may cause the battery to rust.
●Do not touch or move any other component inside the remote control.
●Do not bend either of the battery terminals.