Page 560 of 628

5608-2. Steps to take in an emergency
IS300h_EE(OM53D56E)
One of the following may be the cause of the problem:
●The electronic key may not be functioning properly. (→P. 5 6 4 )
●There may not be sufficient fuel in the vehicle’s tank.
Refuel the vehicle.
●There may be a malfunction in the immobilizer system. ( →P. 9 0 )
●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 sys-
tem. ( →P. 5 6 1 )
One of the following may be the cause of the problem:
●The 12-volt battery terminal connections may be loose or corroded.
●The 12-volt battery may be discharged. ( →P. 5 6 6 )
If the hybrid system will not start
Reasons for the hybrid system not starting vary depending on the situation.
Check the following and perform the appropriate procedure:
The hybrid system will not start even though the correct starting proce-
dure is being followed. ( →P. 212)
The interior lights and headlights are dim, or the horn does not sound or
sounds at a low volume.
Page 561 of 628

5618-2. Steps to take in an emergency
8
When trouble arises
IS300h_EE(OM53D56E)
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. 5 6 6 )
Contact any authorized Lexus dealer or repairer, or another duly qualified and
equipped professional if the problem cannot be repaired, or if repair procedures 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 nor-
mally:
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 any authorized Lexus dealer or
repairer, or another duly qualified and equipped professional.
The interior lights and he adlights do not turn on, or the horn does not
sound.
Emergency start function
1
2
3
4
Page 567 of 628
5678-2. Steps to take in an emergency
8
When trouble arises
IS300h_EE(OM53D56E)
Open the exclusive jump starting
terminal cover.
Connect the jumper cables according to the following procedure:Connect a positive jumper cable clamp to the exclusive jump starting ter-
minal on your vehicle.
Connect the clamp on the other end of the positive cable to the positive (+)
battery terminal on the second vehicle.
Connect a negative cable clamp to the negative (-) battery terminal on the
second vehicle.
Connect the clamp at the other end of the negative cable to a solid, station-
ary, unpainted metallic point away from the exclusive jump starting terminal
and any moving parts, as shown in the illustration.
Start the engine of the second vehicle. Increase the engine speed slightly and
maintain at that level for approximately 5 minutes to recharge the 12-volt bat-
tery of your vehicle.
Open and close any of the doors of your vehicle with the power switch off.3
4
1
2
3
4
5
6
Page 568 of 628

5688-2. Steps to take in an emergency
IS300h_EE(OM53D56E)
Maintain the engine speed of the second vehicle and start the hybrid system
of your vehicle by turning the power switch to ON mode.
Make sure the “READY” indicator comes on. If the indicator does not come
on, contact any authorized Lexus dealer or repairer, or another duly qualified
and equipped professional.
Once the hybrid system has started, remove the jumper cables in the exact
reverse order from which they were connected.
Once the hybrid system starts, have the vehicle inspected at any authorized
Lexus dealer or repairer, or another duly qualified and equipped professional as
soon as possible.
■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.
■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 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 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 mo de 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 dis-
charged, be especially careful when reconnecting the 12-volt battery.
7
8
9
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5698-2. Steps to take in an emergency
8
When trouble arises
IS300h_EE(OM53D56E)
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.
■12-volt battery precautions
The 12-volt battery contains poisonous and corrosive acidic electrolyte, while related
parts contain lead and lead compounds. Observe 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 any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional 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 detrimental to the health of passengers.
■When replacing the 12-volt battery
→ P. 4 6 5
Page 584 of 628
5849-1. Specifications
IS300h_EE(OM53D56E)
*: The fluid capacity is a reference quantity. If replacement is necessary, contact any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional.
Electrical system
12-volt battery
Open voltage at 20 °C
(68 °F):
12.5 V or higher: Fully charged
11.0 - 12.4 V: Half charged
10.9 V or lower: Discharged
(Check the voltage 20 minutes after the hybrid system
and all lights are turned off.)
Charging rates4 A — 5 A
Hybrid transmission
Fluid capacity*3.8 L (4.0 qt., 3.3 Imp. qt.)
Fluid typeTo y o t a G e n u i n e AT F W S
NOTICE
■Hybrid transmission fluid type
Using transmission fluid other than “Toyota Genuine ATF WS” may cause deterioration
in shift quality, locking up of your transmission accompanied by vibration, and ulti-
mately damage the hybrid transmission of your vehicle.
Page 588 of 628
5889-1. Specifications
IS300h_EE(OM53D56E)
Light bulbs*1
Light bulbsWTy p e
Exterior
Discharge headlights*235A
Front turn signal lights21B
Rear turn signal lights21B
Back-up lights16C
Outer foot lights5C
Interior
Door courtesy lights5C
Vanity lights8C
Interior light8C
Personal lights8C
Footwell lights3.8C
Trunk light*25C
A: D4S discharge bulbs B: Wedge base bulbs (amber)
C: Wedge base bulbs (clear)
*1: Light bulbs not listed in this table are LED bulbs.
*2: If equipped
Page 589 of 628
589
9
9-1. Specifications
Vehicle specifications
IS300h_EE(OM53D56E)
■Use of ethanol blended gasoline in a gasoline engine
Lexus allows the use of ethanol blended gasoline where the ethanol content is up to 10%.
Make sure that the ethanol blended gasoline to be used has a Research Octane Number
that follows the above.
■If your engine knocks
●Consult any authorized Lexus dealer or repairer, or another duly qualified and
equipped professional.
●You may occasionally notice light knocking fo
r a short time while accelerating or driv-
ing uphill. This is normal and there is no need for concern.
Fuel information
EU area:
You must only use unleaded gasoline conforming to European standard
EN228.
Select unleaded gasoline with a Research Octane Number of 95 or higher
for optimum engine performance.
Except EU area:
You must only use unleaded gasoline.
Select unleaded gasoline with a Research Octane Number of 95 or higher
for optimum engine performance.