2016 LEXUS RX450H battery

4756-3. Do-it-yourself maintenance
6
Maintenance and care
RX450h_U_OM0E013U
■12-volt battery
P. 483
Engine compartment
Washer fluid tank ( P. 482)
Brake fluid reservoir ( P. 481)
Engine oil level dipstick (P. 476)
Engine coolant reservoir (P. 479)
Power control unit coolant reservoir ( P. 479) Fuse boxes (
P. 508)
Radiator ( P. 480)
Power control unit coolant
radiator ( P. 480)
Condenser ( P. 480)
Electric cooling fans
Engine oil filler cap ( P. 477)1
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4836-3. Do-it-yourself maintenance
6
Maintenance and care
RX450h_U_OM0E013U
The 12-volt battery is located in the
left-hand side of luggage compart-
ment.Lift the deck board and attach the hook. ( P. 430)
Remove the cover after removing
the clips. Press
Pull out
12-volt battery
Location
Removing the 12-volt battery cover
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4846-3. Do-it-yourself maintenance
RX450h_U_OM0E013U
Make sure that the 12-volt battery terminals are not corroded and that there are
no loose connections, cracks, or loose clamps. Terminals
Hold-down clamp
Install the 12-volt battery cover with the
clips. 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 charge r 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 mechan ical key to lock/unlock the doors.
●Start the hybrid system with the power sw itch 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
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Installing the 12-volt battery cover
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4856-3. Do-it-yourself maintenance
6
Maintenance and care
RX450h_U_OM0E013U
●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 connec ting the 12-volt battery if the power switch
mode prior to discharge is unknown.
If the system will not start even after multip le attempts at all methods above, contact your
Lexus dealer.
WARNING
■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 matc h 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 emergenc y medical attention immedi-
ately.
■When handling the 12-volt battery
 P. 572

4866-3. Do-it-yourself maintenance
RX450h_U_OM0E013U
WARNING
■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 touch the positive (+) ter-
minal, which may cause a short and result in
death or serious injury.

5066-3. Do-it-yourself maintenance
RX450h_U_OM0E013U
●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.
Electronic key battery
Replace the battery with a new one if it is depleted.
You will need the following items:
Replacing the battery
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5076-3. Do-it-yourself maintenance
6
Maintenance and care
RX450h_U_OM0E013U
■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.
■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.
WARNING
■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 coul d result in death or serious injury.
NOTICE
■For normal operation after 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 co mponent inside the remote control.
●Do not bend either of the battery terminals.

5096-3. Do-it-yourself maintenance
6
Maintenance and care
RX450h_U_OM0E013U
Luggage compartment (type A fuse box)
Remove the 12-volt battery cover.
( P. 483)
Luggage compartment (type B fuse box)
Remove the terminal cover.
Remove the fuse with the pullout
tool.
Only some fuses can be removed
using the pullout tool.
Check if the fuse is blown.Normal fuse
Blown fuse
Replace the blown fuse with a new
fuse of an appropriate amperage rat-
ing. The amperage rating can be
found on the fuse box lid.
Many types of fuse are used on this
vehicle. This illustration shows a com-
mon type of fuse used on this vehicle.
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