Lexus ES 300h Owner's Manual page 478

To prevent 12-volt battery discharge
■
● Turn off the headlights and the audio sys-
tem while the hybrid system is stopped.
Turn off any unnecessary electrical com-
●
ponents when the vehicle is running at a
low speed for an extended period, such
as in heavy traffic.
■ When the 12-volt battery is removed or
discharged
Information stored in the ECU is cleared.
●
When the 12-volt battery is depleted,
have the vehicle inspected at your Lexus
dealer.
● Some systems may require initialization.
(P.511)
When removing the 12-volt battery ter-
■
minals
When the 12-volt battery terminals are
removed, the information stored in the
ECU is cleared. Before removing the 12-
volt battery terminals, contact your Lexus
dealer.
Charging the 12-volt battery
■
The electricity stored in the 12-volt battery
will discharge gradually even when the
vehicle is not in use, due to natural dis-
charge and the draining effects of certain
electrical appliances. If the vehicle is left for
a long time, the 12-volt battery may dis-
charge, and the hybrid system may be
unable to start. (The 12-volt battery
recharges automatically during driving.)
■ When recharging or replacing the 12-
volt battery
In some cases, it may not be possible to
●
unlock the doors using the smart entry &
start system when the 12-volt battery is
discharged. Use the wireless remote
control or the mechanical key to lock or
unlock the doors.
● The hybrid system may not start on the
first attempt after the 12-volt battery has
recharged but will start normally after the
second attempt. This is not a malfunction.
The power switch mode is memorized by
●
the vehicle. When the 12-volt battery is
reconnected, the system will return to the
7-2. Steps to take in an emergency
mode it was in before the 12-volt battery
was discharged. Before disconnecting
the 12-volt battery, turn the power switch
off.
If you are unsure what mode the power
switch was in before the 12-volt battery
discharged, be especially careful when
reconnecting the 12-volt battery.
When replacing the 12-volt battery
■
Use a Central Degassing type 12-volt
●
battery (European Regulations).
● Use a 12-volt battery that the case size is
same as the previous one (LN2), 20 hour
rate capacity (20HR) is equivalent
(60Ah) or greater, and performance rat-
ing (CCA) is equivalent (345A) or
greater.
• If the sizes differ, the 12-volt battery can-
not be properly secured.
• If the 20 hour rate capacity is low, even if
the time period where the vehicle is not
used is a short time, the 12-volt battery
may discharge and hybrid system may
not be able to start.
Use a 12-volt battery with a handle. If a
●
12-volt battery without a handle is used,
removal is more difficult.
● After replacing, firmly attach the follow-
ing items to the exhaust hole of the 12-
volt battery.
• Use the exhaust hose that was attached
to the 12-volt battery before exchanging.
• Use the exhaust hole plug included with
the 12-volt battery exchanged or the one
installed on the battery prior to the
exchange. (Depending on the 12-volt
battery to be exchanged, the exhaust
hole may be plugged.)
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