2006 Lexus IS250 engine

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2-1. Driving procedures
■If the engine does not start
The engine immobilizer system may not have been deactivated. (P. 5 0 )
■When the engine switch indicator flashes in amber
The system may be malfunctioning. Have the vehicle inspected by your Lexus
dealer immediately.
■Auto power OFF function
The engine switch will auto matically turn OFF when left in ACC mode for 1 hour or
more.
■Electronic key battery depletion
 P. 8
■When the electronic key battery is discharged
P. 2 9 3
■Conditions affecting operation
P. 6
CAUTION
■When starting the engine
Always start the engine while sitting in the driver’s seat. Do not press the accelera-
tor while starting the engine under any circumstances.
Doing so may cause an accident resu lting in death or serious injury.
■Caution when driving
Do not touch the engine switch while driving.
Pressing and holding the engine switch will stop the engine, which may lead to an
unexpected accident.

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2-1. Driving procedures
2
When driving
NOTICE
■To prevent battery discharge
Do not leave the engine switch in ACC or IG-ON mode for long periods without
the engine running.
■When starting the engine
●Do not race a cold engine.
●If the engine becomes difficult to start or stalls frequently, have the engine
checked immediately.

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2-1. Driving procedures
Automatic Transmission (if equipped)
Select a shift position appropriate for the driving conditions.
■Shifting the shift lever
While the engine switch
is in IG-ON mode,
depress the brake pedal
and move the shift lever.

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2-1. Driving procedures
2
When driving
■Shift position uses
*1: To improve fuel consumption and reduce noises, set the shift lever in the D
position for normal driving.
*2: Selecting shift ranges using S mode re stricts the upper limit of the possible
gear ranges, controls engine brakin g forces, and prevents unnecessary
upshifting.
■ Selecting a driving mode
The following patterns can be selec ted to suit current driving and
operating conditions.
Power mode
For powerful acceleration
and driving in mountainous
regions.
Normal mode
Snow mode
For accelerating and driving
on slippery road surfaces,
such as on snow.
Press SNOW to return to nor-
mal mode.
Shift positionFunction
PParking the vehicle or starting the engine
RReversing
NNeutral
DNormal driving*1
SS mode driving*2 ( P. 9 4 )

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2-1. Driving procedures
Changing shift ranges in S modeShift the shift lever to the S position and operate the shift lever or shift
paddle switch. Upshifting
Downshifting
The initial shift range in S mode is auto matically set to 5 or 4 according to
vehicle speed. However, the initial shift range may be set to 3 or 2 if the
AI-SHIFT has operated while the shift lever was in the D position.
( P. 9 5 )
■ Shift ranges and their functions
A lower shift range will provide greater engine braking forces than a higher shift
range.
Shift rangeFunction
6Automatically selecting gears between 1 and 6
according to vehicle speed and driving conditions.
5Automatically selecting gears between 1 and 5
according to vehicle speed and driving conditions.
4Automatically selecting gears between 1 and 4
according to vehicle speed and driving conditions.
3Automatically selecting gears between 1 and 3
according to vehicle speed and driving conditions.
2Automatically selecting gears between 1 and 2
according to vehicle speed and driving conditions.
1Setting the gear at 1.

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2-1. Driving procedures
2
When driving
■Gear position display when driving in S mode
The current gear is displayed on the multi-information display. ( P. 112)
■Downshifting restrictions wa rning buzzer (in the S mode)
To help ensure safety and driving perfor mance, downshifting operation may some-
times be restricted. In some circumstances, downshifting may not be possible even
when the shift lever or shift paddle switch is operated. (The warning buzzer will
sound twice.)
■When driving with the cruise control system or dynamic radar cruise control sys-
tem
The engine brake will not operate in the S mode, even when downshifting to 5 or 4.
(  P. 121, 124)
■SNOW mode automatic deactivation
SNOW mode is automatically deactivated if the engine switch is turned to ACC or
IG-ON mode after driving in SNOW mode.
■If the shift lever cannot be shifted from P
 P. 3 5 7
■If the indicator does not come on even after shifting the shift lever to S
This may indicate a malfunction in the automatic transmission system. Have the
vehicle inspected by your Lexus dealer immediately.
(In this situation, the vehicle will operate as if the shift lever is in D.)
■AI-SHIFT
The AI-SHIFT automatically shifts the gear to the optimal position according to the
driver performance and driving conditions.
The AI-SHIFT automatically operates when th e shift lever is in the D position. (Shift-
ing the shift lever to the S position cancels the function.)

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2-1. Driving procedures
2
When driving
■Recommended shifting speed
The following table indicates shifting speeds for optimum fuel economy.
mph (km/h)
■Maximum downshifting speed
Adhere to the downshifting speeds in the following table in order to prevent over-
revving the engine.
mph (km/h)
Shifting operationRecommended speed
1
215 (24)
2
325 (40)
3
440 (64)
4
545 (72)
5
650 (80)
Shift positionMaximum speed
133 (54)
256 (90)
383 (134)
4108 (172)

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2-1. Driving procedures
Turn signal lever
■Turn signals can be operated when
The engine switch is in IG-ON mode.
■If the indicators flash faster than usual
Check that a light bulb in the front or rear turn signal lights has not burned out.
Left turn
Right turn
Move and hold the lever part-
way to signal a lane change
The left hand signal will flash
until you release the lever.
Move and hold the lever part-
way to signal a lane change
The right hand signal will flash
until you release the lever.