2012 Lexus IS250 Battery

5
When trouble arises
501
5-2. Steps to take in an emergency
IS350/250_U
If the engine will not start
If the engine will not start even though correct starting procedures are
being followed (
→P. 141), consider each of the following points.
■The engine will not start even when the starter motor operates
normally.
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 once more following correct starting
procedures. ( →P. 141)
● There may be a malfunction in the engine immobilizer system.
(→ P. 9 0 )
■ The starter motor turns over slowly, the interior lights and head-
lights are dim, or the horn does not sound or sounds at a low vol-
ume.
One of the following may be the cause of the problem.
● The battery may be discharged. ( →P. 5 1 0 )
● The battery terminal connections may be loose or corroded.

502
5-2. Steps to take in an emergency
IS350/250_U
■The starter motor does not turn ov er, the interior lights and head-
lights do not turn on, or the horn does not sound.
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. 5 1 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.

5
When trouble arises
505
5-2. Steps to take in an emergency
IS350/250_U
If the electronic key does not operate properly
Locking and unlocking the doors, unlocking the trunk and key linked functions
Use the mechanical key built in to the electronic keys to operate the
doors. (→P. 2 9 )
Doors Remove the cover on the driver’s
door handle.
Locks all the doors
Closes the windows and moon
roof (turn and hold)
Unlocks the door
Turning the key rearward unlocks
the driver's door. Turning the key
once again unlocks the other
doors.
Opens the windows and moon
roof (turn and hold)
If communication between the electronic key and vehicle is interrupted
(→ P. 37) or the electronic key cannot be used because the battery is
depleted, the smart access system with push-button start and wireless
remote control cannot be used. In such cases, the doors and trunk can be
opened or the engine can be started by following the procedure below.
STEP1
STEP2

5
When trouble arises
509
5-2. Steps to take in an emergency
IS350/250_U
■Stopping the engine
For vehicles with an automatic transmission: Shift the shift lever to P and press the
“ENGINE START STOP” switch as you normally do when stopping the engine.
For vehicles with a manual transmission: Shift the shift lever to N position and press
the “ENGINE START STOP” switch as you normally do when stopping the engine.
■Replacing the key battery
As the above procedure is a temporary measure, it is recommended that the elec-
tronic key battery be replaced immediately when the battery depletes.
(→ P. 4 3 3 )

510
5-2. Steps to take in an emergency
IS350/250_U
If the vehicle battery is discharged
The following procedures may be used to start the engine if the vehicle’s
battery is discharged.
You can call your Lexus dealer or a qualified repair shop.
If you have a set of jumper (or booster) cables and a second vehicle
with a 12-volt battery, you can jump start your Lexus following the steps
below.
Remove the engine compartment covers. ( →P. 399)
Connecting the jumper cables.
Positive (+) battery terminal on your vehicle
Positive (+) battery terminal on the second vehicle
Negative (-) battery terminal on the second vehicle
Connect the jumper cable to ground on your vehicle 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 with the “ENGINE START
STOP” switch OFF.
STEP1
STEP2
STEP3
STEP4

5
When trouble arises
511
5-2. Steps to take in an emergency
IS350/250_U
■Avoiding a discharged battery
●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, etc.
■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.)
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 the jumper cable is connected to the correct terminal and that it is not
unintentionally in contact with any part other than the intended terminal.
●Do not allow the jumper cables to come into contact with the “+” and “-” termi-
nals.
●Do not allow open flame or use matches, cigarette lighters or smoke near the
battery.
Maintain the engine speed of the second vehicle and turn the
“ENGINE START STOP” switch to IGNITION ON mode,
then start the vehicle’s engine.
Once the vehicle’s engine has started, remove the jumper
cables in the exact reverse order in which they were con-
nected.
Once the engine starts, have the vehicle checked at your Lexus dealer
as soon as possible.STEP5
STEP6

512
5-2. Steps to take in an emergency
IS350/250_U
CAUTION
■Battery precautions
The battery contains poisonous and corrosive acidic electrolyte, while related parts
contain lead and lead compounds. Observe the following precautions when han-
dling 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 vehi-
cle body.
●Do not lean over the battery.
●In the event that 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 battery support, terminals, and other
battery-related parts.
●Do not allow children near the battery.
NOTICE
■To prevent damaging the vehicle
Do not pull- or push-start the vehicle, because the three-way catalytic converter
may overheat and become a fire hazard.
■When handling jumper cables
Be careful that the jumper cables do not become tangled in the cooling fan or any
of the belts when connecting or disconnecting them.

528
6-1. Specifications
IS350/250_U
Electrical system
Differential
Front
Rear
*: Your Lexus vehicle is filled with “Toyota Genuine Differential Gear Oil” at the factory. Use Lexus approved “Toyota Genuine Differential Gear Oil” or an
equivalent of matching quality to satisfy the above specification. Please contact
your Lexus dealer for further details.
Battery
Open voltage* at
68 °F (20 °C):12.6  12.8 V Fully charged
12.2 
12.4 V Half charged
11.8 
12.0 V Discharged
(*: Voltage checked 20 minutes after
the engine and all the lights are turned
off)
Charging rates5 A max.
Oil capacity0.74 qt. (0.70 L, 0.61 Imp. qt.)
Oil typeHypoid gear oil API GL-5
Oil viscosityAbove 0 °F (-18 °C): SAE90
Below 0 °F (-18 °C): SAE80W or SAE80W-90
Oil capacity
IS350:
1.42 qt. (1.35 L, 1.19 Imp. qt.)
IS250:
1.20 qt. (1.15 L, 1.01 Imp. qt.)
Oil type and viscosity*Toyota Genuine Differential Gear Oil LT 75W-85
GL-5 or equivalent