2018 LEXUS RC350 battery

4086-3. Do-it-yourself maintenance
RC350_RC300 AWD_RC3 00_RC F_U(OM24748U)
Check the battery as follows.
■Battery exterior
Make sure that the battery terminals are not corroded and that there are no
loose connections, cracks, or loose clamps.
Terminals
Hold-down clamp
■Checking battery condition (vehic les with the battery indicator)
Check the battery condition by indicator color.
Blue: Good condition
Red: Not working properly.
Have the battery checked by your
Lexus dealer.
White: Charging is necessary.
Have the vehicle inspected by
your Lexus dealer.
Battery
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4096-3. Do-it-yourself maintenance
RC350_RC300 AWD_RC3 00_RC F_U(OM24748U)
6
Maintenance and care
■Before recharging
When recharging, the battery produces hydrogen gas which is flammable and explosive.
Therefore, observe the following before recharging:
●If recharging with the 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 battery.
■After recharging/reconnecting the battery
The engine may not start. Follow the procedure below to initialize the system.
Shift the shift lever to P.
Open and close either door.
Restart the engine.
●Unlocking the doors using the smart access system with push-button start may not be
possible immediately after reconnecting the battery. If this happens, use the wireless
remote control or the mechanical key to lock/unlock the doors.
●Start the engine with the engine switch in ACCESSORY mode. The engine may not
start with the engine switch turned off. However, the engine will operate normally from
the second attempt.
●The engine switch mode is recorded by the vehicle. If the battery is disconnected and
reconnected, the vehicle will return the engi ne switch mode to the status it was in
before the battery was disconnected. Make su re to turn off the engine before discon-
necting the battery. Take extra care when connecting the battery if the engine switch
mode prior to the battery being disconnected is unknown.
If the system will not start even after mult iple attempts, contact your Lexus dealer.
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4106-3. Do-it-yourself maintenance
RC350_RC300 AWD_RC3 00_RC F_U(OM24748U)
WARNING
■Chemicals in the battery
Batteries contain 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 wo rking on or near the battery:
●Do not cause sparks by touching the battery terminals with tools.
●Do not smoke or light a match near the battery.
●Avoid contact with eyes, skin and clothes.
●Never inhale or swallow electrolyte.
●Wear protective safety glasses when working near the battery.
●Keep children away from the battery.
■Where to safely charge the battery
Always charge the battery in an open area . Do not charge the battery in a garage or
closed room where there is insufficient ventilation.
■How to recharge the battery
Only perform a slow charge (5 A or less) . The 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 s kin. 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.
NOTICE
■When recharging the battery
Never recharge the battery while the engine is running. Also, be sure all accessories
are turned off.

4276-3. Do-it-yourself maintenance
RC350_RC300 AWD_RC3 00_RC F_U(OM24748U)
6
Maintenance and care
●Flathead screwdriver
●Small flathead screwdriver
●Lithium battery CR2032
Take out the mechanical key.
Remove the cover.
To prevent damage to the key, wrap the
tip of the screwdriver with 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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4286-3. Do-it-yourself maintenance
RC350_RC300 AWD_RC3 00_RC F_U(OM24748U)
■Use a CR2032 lithium battery
●Batteries can be purchased at your Lexus dealer, loca l electrical appliance shops or
camera stores.
●Replace only with the same or equivalent type recommended by the manufacturer.
●Dispose of used batteries according to 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 rang e 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.

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When trouble arises7
RC350_RC300 AWD_RC300_RC F_U(OM24748U)
7-1. Essential information
Emergency flashers .................. 442
If your vehicle has to be stopped in
an emergency .......................... 443
7-2. Steps to take in an emergency
If your vehicle needs to be towed ........................................... 444
If you think something is wrong ............................................ 451
Fuel pump shut off system ...... 452
If a warning light turns on or a warning buzzer
sounds.......................................... 453
If a warning message is displayed.....................................460
If you have a flat tire (vehicles with a
spare tire) ...................................489
If you have a flat tire (vehicles with
an emergency
tire puncture repair kit) ........502
If the engine will not start ......... 516
If the electronic key does not operate properly .............. 518
If the vehicle battery is discharged ................................. 522
If your vehicle overheats ......... 526
If the vehicle becomes stuck ............................................. 532

442
RC350_RC300 AWD_RC300_RC F_U(OM24748U)
7-1. Essential information
Press the switch.
All the turn signals will flash.
To turn them off, press the switch once
again.
■Emergency flashers
If the emergency flashers are used for a long time while the engine is not operating, the
battery may discharge.
Emergency flashers
The emergency flashers are used to warn other drivers when the vehicle has
to be stopped in the road due to a breakdown, etc.

4577-2. Steps to take in an emergency
RC350_RC300 AWD_RC3 00_RC F_U(OM24748U)
7
When trouble arises
■SRS warning light
This warning light system monitors the airbag sensor assembly, front impact sensors, side
impact sensors (door), side impact sensors (front), side im pact sensors (rear), driver’s
seat position sensor, driver’s seat belt buckle switch, front passenger occupant classifica-
tion system, “AIR BAG ON” indicator light, “A IR BAG OFF” indicator light, front passen-
ger’s seat belt buckle switch, seat belt pretensioners, airbags, interconnecting wiring and
power sources. ( P. 41)
■Front passenger detection sensor, seat belt reminder and warning buzzer
If luggage is placed on the front passenger seat, the front passenger detection sensor
may cause the warning light to flash and the warning buzzer to sound even if a passenger
is not sitting in the seat.
■If the malfunction indicator lamp comes on while driving
First check the following:
●Is the fuel tank empty?
If it is, fill the fu el tank immediately.
●Is the fuel tank cap loose?
If it is, tighten it securely.
The light will go off after several driving trips.
If the light does not go off even after severa l trips, contact your Lexus dealer as soon as
possible.
■Electric power steering system warning light (warning buzzer)
When the battery charge becomes insufficien t or the voltage temporarily drops, the
electric power steering system warning li ght may come on and the warning buzzer may
sound.
■When the tire pressure warning light comes on
Check the tire inflation pressu re and adjust to the appropriate level. Pushing the tire
pressure warning reset switch will not tu rn off the tire pressure warning light.
■The tire pressure warning light may come on due to natural causes
The tire pressure warning light may come on due to natural causes such as natural air
leaks and tire inflation pressure changes caus ed by temperature. In this case, adjusting
the tire inflation pressure will turn off the warning light (after a few minutes).
■When a tire is replaced with the spare tire (if equipped)
The spare tire is not equipped with a tire pr essure warning valve and transmitter. If a tire
goes flat, the tire pressure warning light will not turn off even though the flat tire has been
replaced with the spare tire.
■Conditions that the tire pressure wa rning system may not function properly
 P. 417
■If the tire pressure warning light freque ntly comes on after blinking for 1 minute
If the tire pressure warning light frequently comes on after blinking for 1 minute when the
engine switch is turned to IGNITION ON mo de, have it checked by your Lexus dealer.
■Warning buzzer
In some cases, the buzzer may not be heard due to being in a noisy location or audio
sound.