Page 460 of 608
460
ES300h_OM_OM33D45U_(U)7-3. Do-it-yourself maintenance
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.
Page 512 of 608
5128-2. Steps to take in an emergency
ES300h_OM_OM33D45U_(U)
■If “See Owner’s Manual” is shown
●If the following message is shown, following the instructions, accordingly.
• “Engine Coolant Temp High” ( →P. 531)
●If the following messages are sh own, there may be a malfunction.
Immediately have the vehicle inspected by your Lexus dealer.
• “Check Access System with Elec. Key”
• “Hybrid System Malfunction”
●If the following messages are sh own, there may be a malfunction.
Immediately stop the vehicle in a safe place and contact your Lexus dealer. Continuing
to drive the vehicle may be dangerous.
• “Braking Power Low Stop in a Safe Place”
• “Charging System Malfunction”
• “Oil Pressure Low Stop in a Safe Place”
■Warning buzzer
In some cases, the buzzer may not be heard because of noisy place or an audio sound.
Page 529 of 608

5298-2. Steps to take in an emergency
ES300h_OM_OM33D45U_(U)
8
When trouble arises
■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 stopped.
●Turn off any unnecessary electrical components when the vehicle is running at a low
speed for an extended period , such as in heavy traffic.
■Charging the 12-volt battery
The electricity stored in the 12-volt battery w ill discharge gradually even when the vehicle
is not in use, due to natural discharge and the draining effects of certain electrical appli-
ances. If the vehicle is left for a long time, the 12-volt battery may discharge, and the
hybrid system may be unable to start. (The 12-volt battery recharges automatically while
the hybrid system is operating.)
■When recharging or replacing the 12-volt battery
●In some cases, it may not be possible to un lock the doors using the smart access system
with push-button start 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 retu rn to the mode it was in before the 12-volt battery was
discharged. Before disconne cting 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 dis-
charged, be especially careful when reconnecting the 12-volt battery.
Page 530 of 608

5308-2. Steps to take in an emergency
ES300h_OM_OM33D45U_(U)
WARNING
■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 cab le 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 jump er cables to come into contact with each
other.
●Do not smoke, use matches, cigarette light ers or allow open flame near the 12-volt
battery.
■12-volt battery precautions
The 12-volt battery contains poisonous and co rrosive acidic electrolyte, while related
parts contain lead and lead compounds. Ob serve the following precautions when han-
dling the 12-volt battery:
●When working with the 12-volt battery, always wear safety glasses and take care not
to allow any 12-volt battery fluids (acid) to come into contact with skin, clothing or the
vehicle body.
●Do not lean over the 12-volt battery.
●In the event that 12-volt battery fluid comes into contact with the skin or eyes, immedi-
ately wash the affected area with water and seek medical attention.
Place a wet sponge or cloth over the affected area until medical attention can be
received.
●Always wash your hands after handling the 12-volt battery support, terminals, and
other battery-related parts.
●Do not allow children near the 12-volt battery.
■After recharging the 12-volt battery
Have the 12-volt battery inspected at yo ur Lexus dealer as soon as possible.
If the 12-volt battery is deteriorating, continued use may cause the 12-volt battery to
emit a malodorous gas, which may be de trimental to the health of passengers.
■When replacing the 12-volt battery
→P. 459
Page 543 of 608
ES300h_OM_OM33D45U_(U)
5439-1. Specifications
9
Vehicle specifications
Cooling system
Capacity
Gasoline
engine7.6 qt. (7.2 L, 6.3 Imp.qt.)
Power
control unit
3.4 qt. (3.2 L, 2.8 Imp.qt.)
Coolant type
Use either of the following:
• “Toyota Super Long Life Coolant”
• Similar high-quality ethylene glycol-based non-sili-
cate, non-amine, non-nitrite, and non-borate cool-
ant with long-life hybrid organic acid technology
Do not use plain water alone.
Ignition system
Spark plug
MakeDENSO FK16HR-A8
Gap0.031 in. (0.8 mm)
NOTICE
■Iridium-tipped spark plugs
Use only iridium-tipped spark plugs. Do not adjust the spark plug gap.
Electrical system
12-volt battery
Open voltage at 68°F
(20° C):12.0 V or higher
(Voltage is checked 20 minutes after the hybrid system
and all lights are turned off.)
Charging rates5 A max.