Page 486 of 573

4858-2. Steps to take in an emergency
8
When trouble arises
IS350/250_U (OM53758U)
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. 1 5 9 )
●There may be a malfunction in the engine immobilizer system. ( P. 6 9 )
One of the following may be the cause of the problem:
●The battery terminal connections may be loose or corroded.
●The battery may be discharged. ( P. 4 9 0 )
The engine starting system may be malfun ctioning due to an electrical problem
such as electronic key battery depletion or a blown fuse. However, an interim
measure is available to start the engine. ( P. 4 8 6 )
If the engine will not start
If the engine will not start even though correct starting procedures are being
followed ( P. 159), consider each of the following points:
The engine will not start even thoug h the starter motor operates nor-
mally.
The starter motor turns over slowly , the interior lights and headlights
are dim, or the horn does not sound or sounds at a low volume.
The starter motor does not turn over
Page 487 of 573

4868-2. Steps to take in an emergency
IS350/250_U (OM53758U)
One of the following may be the cause of the problem:
●One or both of the battery terminals may be disconnected.
●The battery may be discharged. (P. 4 9 0 )
●There may be a malfunction in the steering lock system.
Contact your Lexus dealer if the problem cannot be repaired, or if repair procedures
are unknown.
When the engine does not start, the following steps can be used as an interim
measure to start the engine if the engine switch is functioning normally:
Set the parking brake.
Shift the shift lever to P.
Turn the engine switch to ACCESSORY mode.
Press and hold the engine switch for about 15 seconds while depressing the
brake pedal firmly.
Even if the engine can be started using the above steps, the system may be mal-
functioning. Have the vehicle inspected by your Lexus dealer.
The starter motor does not turn over, the interior lights and headlights
do not turn on, or the horn does not sound.
Emergency start function
1
2
3
4
Page 492 of 573

4918-2. Steps to take in an emergency
8
When trouble arises
IS350/250_U (OM53758U)
Connect the jumper cables according to the following procedure:Connect a positive jumper cable clamp to the positive (+) battery terminal
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 battery 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 battery of
your vehicle.
Open and close any of the doors of your vehicle with the engine switch off.
Maintain the engine speed of the second vehicle and start the engine of your
vehicle by turning the engine switch to IGNITION ON mode.
Once the vehicle’s engine has started, remove the jumper cables in the exact
reverse order from which they were connected.
Once the engine starts, have the vehicle inspected at your Lexus dealer as soon
as possible.3
1
2
3
4
4
5
6
7
Page 493 of 573

4928-2. Steps to take in an emergency
IS350/250_U (OM53758U)
■Starting the engine when the battery is discharged
The engine cannot be started by push-starting.
■To prevent battery discharge
●Turn off the headlights and the audio system while the engine 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 battery
The electricity stored in the 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 battery may discharge, and the engine may be
unable to start. (The battery recharges automatically during driving.)
■When recharging or replacing the battery
●Make sure that the key is not inside the vehicle when recharging or replacing the bat-
tery. The key may be locked in the vehicle if the alarm is activated. ( P. 7 2 )
●In some cases, it may not be possible to unlock the doors using the smart access system
with push-button start when the battery is discharged. Use the wireless remote control
or the mechanical key to lock or unlock the doors.
●The engine may not start on the first attempt after the battery has recharged but will
start normally after the second attempt. This is not a malfunction.
●The engine switch mode is memorized by the vehicle. When the battery is recon-
nected, the system will return to the mode it was in before the battery was discharged.
Before disconnecting the battery, turn the engine switch off.
If you are unsure what mode the engine switch was in before the battery discharged, be
especially careful when reconnecting the battery.
Page 494 of 573

4938-2. Steps to take in an emergency
8
When trouble arises
IS350/250_U (OM53758U)
CAUTION
■Avoiding battery fires or explosions
Observe the following precautions to prevent accidentally igniting the flammable gas
that may be emitted from the 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 jump er cables to come into contact with each
other.
●Do not smoke, use matches, cigarette lighters or allow open flame near the battery.
■Battery precautions
The battery contains poisonous and corrosive acidic electrolyte, while related parts
contain lead and lead comp ounds. Observe the following precautions when handling
the battery:
●When working with the battery, always wear safety glasses and take care not to allow
any battery fluids (acid) to come into contact with skin, clothing or the vehicle body.
●Do not lean over the battery.
●In the event that battery fluid comes into contact with the skin or eyes, immediately
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 battery support, terminals, and other bat-
tery-related parts.
●Do not allow children near the battery.
NOTICE
■When handling jumper cables
When connecting the jumper cables, ensure th at they do not become entangled in the
cooling fans or engine drive belt.
Page 505 of 573
5049-1. Specifications
IS350/250_U (OM53758U)
■Spark plug
Cooling system
IS250IS350
Capacity 11.1 qt. (10.5 L, 9.2 Imp. qt.) 9.8 qt. (9.3 L, 8.2 Imp. qt.)
Coolant type
Use either of the following:
• “Toyota Super Long Life Coolant”
• Similar high-quality ethylene glycol-based non-silicate,
non-amine, non-nitrite, and non-borate coolant with long-
life hybrid organic acid technology
Do not use plain water alone.
Ignition system
Make DENSO FK20HBR11
Gap0.043 in. (1.1 mm)
NOTICE
■Iridium-tipped spark plugs
Use only iridium-tipped spark plugs. Do not adjust the spark plug gap.
Electrical system
Battery
Open voltage at 68F
(20 C):12.6 12.8 V Fully charged
12.2
12.4 V Half charged
11.8
12.0 V Discharged
(Check the voltage 20 minutes after the engine and all
lights are turned off.)
Charging rates5 A max.
Page 510 of 573
5099-1. Specifications
9
Vehicle specifications
IS350/250_U (OM53758U)
Light bulbs*1
Light bulbsBulb No.WTy p e
Exterior
Discharge headlights*235A
Fog lights*219B
Front turn signal lights7444NA28 /8C
Rear turn signal lights21C
Back-up lights92116D
Outer foot lights5D
Interior
Door courtesy lights1685D
Vanity lights8D
Interior light8D
Pe r s o n a l l i g h t s8D
Footwell lights1943.8D
Trunk light5D
A: D4S discharge bulbsB: H16 halogen bulbs
C: Wedge base bulbs (amber) D: Wedge base bulbs (clear)
*1: Light bulbs not listed in this table are LED bulbs.
*2: If equipped
Page 512 of 573

5119-1. Specifications
9
Vehicle specifications
IS350/250_U (OM53758U)
■Recommendation of the use of gasoline containing detergent additives
●Lexus recommends the use of gasoline that contains detergent additives to avoid the
build-up of engine deposits.
●All gasoline sold in the U.S.A. contains minimum detergent additives to clean and/or
keep clean intake systems, per EPA’s lowest additives concentration program.
●Lexus strongly recommends the use of Top Ti er Detergent Gasoline. For more informa-
tion on Top Tier Detergent Gasoline and a list of marketers, please go to the official
website www.toptiergas.com.
■Recommendation of the use of cleaner burning gasoline
Cleaner burning gasoline, including reformul ated gasoline that contains oxygenates
such as ethanol or MTBE (Methyl Tertiary Butyl Ether) is available in many areas.
Lexus recommends the use of cleaner bu rning gasoline and appropriately blended
reformulated gasoline. These types of gaso line provide excellent vehicle performance,
reduce vehicle emissions and improve air quality.
■Non-recommendation of the use of blended gasoline
●If you use gasohol in your vehicle, be sure th at it has an octane rating no lower than 87.
●Lexus does not recommend the use of gasoline containing methanol.
■Non-recommendation of the use of gasoline containing MMT
Some gasoline contains an octane enhancin g additive called MMT (Methylcyclopenta-
dienyl Manganese Tricarbonyl).
Lexus does not recommend the use of gasolin e that contains MMT. If fuel containing
MMT is used, your emission control system may be adversely affected.
The malfunction indicator lamp on the instru ment cluster may come on. If this happens,
contact your Lexus dealer for service.
■If your engine knocks
●Consult your Lexus dealer.
●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.
●Use only gasoline containing up to 15% etha-
nol.
DO NOT use any flex-fuel or gasoline that
could contain more than 15% ethanol, includ-
ing from any pump labeled E30, E50, E85
(which are only some examples of fuel con-
taining more than 15% ethanol).DO NOT use gasoline con-
taining more than 15% ethanol.
(30% ethanol)
(50% ethanol)
(85% ethanol)