Page 497 of 681

4977-2. Maintenance
7
Maintenance and care
NX300h_U_OM78007UEmission inspection and maintenance (I/M) programsThe OBD system determines that a problem exists somewhere in the emission
control system. Your vehicle may not pa ss the I/M test and may need to be
repaired. Contact your Lexus dealer to service the vehicle. ●
When the 12-volt 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 com-
pletely set. ●
When the fuel tank cap is loose
The malfunction indicator lamp comes on indicating a temporary malfunction
and your vehicle may not pass the I/M test.
The error code in the OBD system will not be cleared unless the vehicle is driven
40 or more times.
Contact your Lexus dealer to prepare the vehicle for re-testing.Some states have vehicle emission inspection programs which include OBD
(On Board Diagnostics) checks. The OBD system monitors the operation of
the emission control system.
If the malfunction indicator lamp comes on
Your vehicle may not pass the I/M test in the following situations:
When the malfunction indicator lamp s till remains on af ter several driv-
ing trips
If your vehicle does not pass the I/M test
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498 7-3. Do-it-yourself maintenance
NX300h_U_OM78007UDo-it-yourself service precautions If you perform maintenance by yourself, be sure to follow the correct proce-
dure as given in these sections. Items Pa 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 681
502 7-3. Do-it-yourself maintenance
NX300h_U_OM78007UEngine compartment
■
12-volt battery
P. 5 1 2Fuse 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 681
512 7-3. Do-it-yourself maintenance
NX300h_U_OM78007U12-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 outLocation
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_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.
Page 515 of 681
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 532 of 681
532 7-3. Do-it-yourself maintenance
NX300h_U_OM78007UElectronic 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