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6956-3. Do-it-yourself maintenance
6
Maintenance and care
■After recharging/reconnecting the 12-volt battery
The engine 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 engine.
●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 mechanical key to lock/unlock the doors.
●Start the engine with the “START STOP ENGINE” switch in ACCESSORY mode.
The engine may not start with the “START STOP ENGINE” switch turned off. How-
ever, the engine will operate normally from the second attempt.
●The “START STOP ENGINE” switch mode is recorded by the vehicle. If the 12-volt
battery is reconnected, the vehicle will return the “START STOP ENGINE” switch
mode to the status it was in before the 12-volt battery was disconnected. Make sure
to turn off the engine before disconnect the 12-volt battery. Take extra care when
connecting the 12-volt battery if the “START STOP ENGINE” switch mode prior to
discharge is unknown.
If the engine will not start even after multiple attempts, contact your Lexus dealer.
CAUTION
■Chemicals in the 12-volt battery
Batteries contain poisonous and corrosive sulfuric acid and may produce hydro-
gen 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.
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ES350_300h_OM_OM33A60U_(U)
6996-3. Do-it-yourself maintenance
6
Maintenance and care
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
■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 discon-
necting 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 mechanical key to lock/unlock the doors.
●Start the hybrid system with the “POWER” switch in ACCESSORY mode. The
hybrid system may not start with the “POWER” switch turned off. However, the
hybrid system will operate normally from the second attempt.
●The “POWER” switch mode is recorded by the vehicle. If the 12-volt battery is recon-
nected, 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”
switch 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.
Exterior
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6-3. Do-it-yourself maintenance
CAUTION
■Chemicals in the 12-volt battery
The 12-volt battery contains poisonous and corrosive sulfuric acid and may pro-
duce 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 bat-
tery 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.
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6-3. Do-it-yourself maintenance
■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 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.
CAUTION
■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 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 component inside the remote control.
●Do not bend either of the battery terminals.
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7
When trouble arises
7-2. Steps to take in an emergency
If the engine will not start (gasoline vehicles)
One of the following may be the cause of the problem:
●There may not be sufficient fuel in the vehicle’s tank.
Refuel the vehicle.
●The engine may be flooded.
Try to restart the engine again following correct starting procedures.
(→P. 201)
●There may be a malfunction in the engine immobilizer system.
(→P. 8 2 )
One of the following may be the cause of the problem:
●The 12-volt battery may be discharged. ( →P. 813)
●The 12-volt battery terminal connections may be loose or corroded.
The engine starting system may be malfunctioning due to an electrical
problem such as electronic key battery depletion or a blown fuse. How-
ever, an interim measure is available to start the engine. ( →P. 8 0 6 )
If the engine will not start even though correct starting procedures are
being followed ( →P. 201), consider each of the following points:
The engine will not start even though the starter motor operates
normally.
The starter motor turns over slowly, the interior lights and head-
lights are dim, or the horn does not sound or sounds at a low vol-
ume.
The starter motor does not turn over
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8067-2. Steps to take in an emergency
ES350_300h_OM_OM33A60U_(U)
One of the following may be the cause of the problem:
●One or both of the 12-volt battery terminals may be disconnected.
●The 12-volt battery may be discharged. (→P. 813)
●There may be a malfunction in the steering lock system.
Contact your Lexus dealer if the problem cannot be repaired, or if repair proce-
dures are unknown.
When the engine does not start, the following steps can be used as an
interim measure to start the engine if the “START STOP ENGINE” switch
is functioning normally:
Set the parking brake.
Shift the shift lever to P.
Turn the “START STOP ENGINE” switch to ACCESSORY mode.
Press and hold the “START STOP ENGINE” switch for about 15 sec-
onds while depressing the brake pedal firmly.
Even if the engine can be started using the above steps, the system may be
malfunctioning. Have the vehicle inspected by your Lexus dealer.
The starter motor does not turn over, the interior lights and head-
lights do not turn on, or the horn does not sound.
Emergency start function
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7
When trouble arises
7-2. Steps to take in an emergency
If the hybrid system will not start (hybrid vehicles)
One of the following may be the cause of the problem:
●The electronic key may not be functioning properly. (→P. 8 1 1 )
●There may not be sufficient fuel in the vehicle’s tank.
Refuel the vehicle.
●There may be a malfunction in the immobilizer system. ( →P. 8 4 )
●There may be a malfunction in the steering lock system.
●The hybrid system may be malfunctioning due to an electrical problem
such as electronic key battery depletion or a blown fuse. However,
depending on the type of malfunction, an interim measure is available
to start the hybrid system. ( →P. 8 0 8 )
One of the following may be the cause of the problem:
●The 12-volt battery may be discharged. ( →P. 8 1 7 )
●The 12-volt battery terminal connections may be loose or corroded.
Reasons for the hybrid system not st arting vary depending on the situa-
tion. Check the following and perform the appropriate procedure:
The hybrid system will not start even though the correct starting
procedure is being followed. ( →P. 2 0 8 )
The interior lights and headlights are dim, or the horn does not
sound or sounds at a low volume.
Page 809 of 918
8087-2. Steps to take in an emergency
ES350_300h_OM_OM33A60U_(U)
One of the following may be the cause of the problem:
●One or both of the 12-volt battery terminals may be disconnected.
●The 12-volt battery may be discharged. (→P. 8 1 7 )
Contact your Lexus dealer if the problem cannot be repaired, or if repair proce-
dures are unknown.
When the hybrid system does not start, the following steps can be used as
an interim measure to start the hybrid system if the “POWER” switch is
functioning normally:
Set the parking brake.
Shift the shift lever to P.
Turn the “POWER” switch to ACCESSORY mode.
Press and hold the “POWER” switch for about 15 seconds while
depressing the brake pedal firmly.
Even if the hybrid system can be started using the above steps, the system
may be malfunctioning. Have the vehicle inspected by your Lexus dealer.
The interior lights and headlights do not turn on, or the horn does
not sound.
Emergency start function
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