Lexus 2012 RX450h Owner's Manual page 927

Starting the hybrid system when the 12-volt battery is discharged
■
The hybrid system cannot be started by push-starting.
To prevent 12-volt battery discharge
■
Turn off the headlights and the audio system while the hybrid system is off.
●
Turn off any unnecessary electrical components 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
■
The power back door must be initialized. (P. 996)
●
The hybrid system may not start. (  P. 762)
●
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 discharge 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 while the hybrid system is operating.)
CAUTION
Avoiding 12-volt battery fires or explosions
■
Observe the following precautions to prevent accidentally igniting the flammable
gas that may be emitted from the 12-volt battery:
Make sure each jumper cable is connected to the correct terminal and that it is
●
not unintentionally in contact with any other than the intended terminal.
Do not allow the other end of the jumper cable connected to the "+" terminal to
●
come into contact with any other parts or metal surfaces in the area, such as
brackets or unpainted metal.
Do not allow the + and - clamps of the jumper cables to come into contact with
●
each other.
Do not smoke, use matches, cigarette lighters or allow open flame near the 12-
●
volt battery.
5-2. Steps to take in an emergency
5
927