2011 Lexus IS250 engine

5
When trouble arises
495
5-2. Steps to take in an emergency
IS350/250_U
Changing “ENGINE START STOP” switch modes and starting the engine
Automatic transmissionShift the shift lever to P and apply the brakes.
Touch the Lexus emblem side of
the electronic key to the
“ENGINE START STOP” switch.
An alarm will sound to indicate that
the start function cannot detect the
electronic key that is touched to
the “ENGINE START STOP”
switch if any of the doors is opened
and closed while the key is touched
to the switch.
To change “ENGINE START STOP” switch modes: Within 10
seconds of the buzzer sounding, release the brake pedal and
press the “ENGINE START STOP” switch. Modes can be
changed each time the switch is pressed.
(→P. 1 3 4 )
To start the engine: Press the “ENGINE START STOP” switch
within 10 seconds after the buzzer sounds, keeping the brake
pedal depressed.
STEP1
STEP2
STEP3

496
5-2. Steps to take in an emergency
IS350/250_UManual transmission
Shift the shift lever to N and depress the clutch pedal.
Touch the Lexus emblem side of
the electronic key to the
“ENGINE START STOP” switch.
An alarm will sound to indicate that
the start function cannot detect the
electronic key that is touched to
the “ENGINE START STOP”
switch if any of the doors is opened
and closed while the key is touched
to the switch.
To change “ENGINE START ST OP” switch modes: Within 10
seconds of the buzzer sounding, release the clutch pedal and
press the “ENGINE START STOP” switch. Modes can be
changed each time the switch is pressed.
(→ P. 1 3 4 )
To start the engine: Press the “ENGINE START STOP” switch
within 10 seconds after the buzzer sounds, keeping the clutch
pedal depressed.
In the event that the engine still cannot be started, contact your Lexus
dealer.
STEP1
STEP2
STEP3

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When trouble arises
497
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 2 1 )

498
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. 388)
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

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When trouble arises
499
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.
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

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When trouble arises
501
5-2. Steps to take in an emergency
IS350/250_U
If your vehicle overheats
If your engine overheats:
Stop the vehicle in a safe place and turn off the automatic air
conditioning system.
Check to see if steam is coming out from under the hood.
If you see steam: Stop the engine. Carefully lift the hood after the steam sub-
sides and then restart the engine.
If you do not see steam: Leave the engine running and carefully lift the hood.
Remove the engine compartment cover. ( →P. 388)
Check to see if the cooling fans are operating.
If the fans are operating: Wait until the temperature of the engine (shown on the
instrument cluster) begins to fall and then stop the engine.
If the fans are not operating: Stop the engine immediately and call your local Lexus
dealer.
After the engine has cooled
down sufficiently, check the
engine coolant level and inspect
the radiator core (radiator) for
any leaks.STEP1
STEP2
STEP3
STEP4
STEP5

502
5-2. Steps to take in an emergency
IS350/250_U
■Overheating
If you observe the following, your vehicle may be overheating.
●The engine coolant temperature gauge enters the red zone or a loss of power is
experienced.
●Steam is coming from under the hood.
CAUTION
■To prevent an accident or injury when inspecting under the hood of your vehicle
●If steam is seen coming from under the hood, do not open the hood until the
steam has subsided. The engine compartment may be very hot, causing serious
injury such as burns.
●Keep hands and clothing away from the fans and other belts while the engine is
running.
●Do not loosen the radiator cap while the engine and radiator are hot.
Serious injury, such as burns, may result from hot coolant and steam released
under pressure.
Add engine coolant if required.
Water can be used in an emer-
gency if engine coolant is
unavailable. (→P. 5 1 5 )
Have the vehicle checked at your nearest Lexus dealer as soon as pos-
sible.
STEP6

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When trouble arises
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5-2. Steps to take in an emergency
IS350/250_U
NOTICE
■When adding engine coolant
Wait until the engine has cooled down before adding engine coolant.
When adding coolant, do so slowly. Adding cool coolant to a hot engine too quickly
can cause damage to the engine.