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Dynamic radar cruise control
Dynamic radar cruise control supplements conventional cruise control
with a vehicle-to-vehicle distance control. In the vehicle-to-vehicle dis-
tance control mode, the vehicle automatically accelerates or decelerates
in order to maintain a set following distance from vehicles ahead.
Indicator
Display
Distance switch
Cruise control switch
: If equipped
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When driving
08_IS350/250_U_(L/O_0808)
■Select cruise mode
Selecting vehicle-to-vehicle dis-
tance control mode
Turn the “ON-OFF” button
on.
Push the button once more to
deactivate.
Selecting conventional con-
stant speed control mode Turn the “ON-OFF” button
on.
Push the button once more to
deactivate.
Vehicle-to-vehicle distance con-
trol mode is always reset when
the “ENGINE START STOP”
switch is switched to IGNITION
ON mode.
Switch to constant speed
control mode.
(push and hold for approxi-
mately one second)
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■Driving in the selected cruise control mode
Accelerate or decelerate to the
desired speed and press the
lever down to set.
■ Adjusting the speed setting
Increase speed
Decrease speed
Hold the lever until the desired
speed setting is displayed.
Fine adjustment of the set speed
can be made by lightly pressing
the lever up or down and releas-
ing it. Adjustment can be made
in increments of approximately
1.0 mph (1.6 km/h) when in the
constant speed control mode,
and approximately 5.0 mph/5.0
km/h when in the vehicle-to-
vehicle distance control mode.
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When driving
08_IS350/250_U_(L/O_0808)
■Canceling and resuming the speed setting
Cancel
Push the lever towards you to
cancel cruise control.
The setting is also canceled
when the brakes are applied.
Resume
To resume cruise control and
return to the set speed, push the
lever up.
■Changing the vehicle- to-vehicle distance
Each push of the switch changes
the vehicle-to-vehicle distance
Long
Medium
Short
The vehicle-to-vehicle distance
is automatically set to the long
mode when the “ENGINE
START STOP” switch is
switched to IGNITION ON
mode.
A mark will be displayed to indi-
cate the presence of the vehicle
if a vehicle is running ahead of
you.
Preceding
vehicle mark
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Driving in vehicle-to-vehicle distance control mode
This mode employs a radar sensor to detect the presence of vehicles
within 328 ft. (100 m) ahead and to judge the distance between your
vehicle and those vehicles.
Note that vehicle-to-vehicle distance will close when traveling on long down-
hill slopes.
Example of constant speed cruising (when there are no vehicles
ahead): When set to 62 mph (100 km/h)
The vehicle travels at the speed set by the driver. The desired vehicle-to-vehi-
cle distance can also be set by operating the vehicle-to-vehicle distance
switch.
Example of deceleration cruising (when the vehicle ahead is driving
slower than the set speed): When fixed speed cruising is set at 62 mph
(100 km/h) and the vehicle ahead is driving at 50 mph (80 km/h)
When a vehicle is detected running ahead of you, in the same lane, the sys-
tem automatically decelerates your vehicle. When a greater reduction in
vehicle speed is necessary, the system applies the brakes. A warning tone
warns you when the system cannot decelerate sufficiently to prevent your
vehicle from closing on the vehicle ahead.
Example of follow-up cruising (when following a vehicle driving slower
than the set speed): When the speed is set to 62 mph (100 km/h) and
the vehicle ahead is driving at 50 mph (80 km/h)
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When driving
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The system continues follow-up cruising while adjusting for changes in the
speed of the vehicle ahead in order to maintain the vehicle-to-vehicle dis-
tance set by the driver.
Example of acceleration (when there are no longer vehicles driving
slower than the set speed in the lane ahead): Wh en the speed is set to
62 mph (100 km/h) and the vehicle ahead driving at 50 mph (80
km/h) is out of the lane
When the vehicle ahead of you executes a lane change, the system slowly
accelerates until the set vehicle speed is reached. The system then returns to
fixed speed cruising.
■Dynamic radar cruise control warning lights, messages and buzzers
Warning lights, messages and buzzers are used to indicate a system malfunction or
to alert you to the need for caution while driving. ( →P. 3 9 2 )
■The dynamic radar cruise can be set when
●The shift lever is in the D position or S position. However, it cannot be set if any
of the ranges 1 through 3 has been selected.
●Vehicle speed is between approximately 30 mph (50 km/h) and 85 mph (135
km/h).
■Accelerating
The vehicle can be accelerated normally. After acceleration, the set speed
resumes.
■Automatically canceling vehicle-to-vehicle distance control
Vehicle-to-vehicle distance control driving is automatically canceled in the follow-
ing situations.
●Vehicle speed falls below 25 mph (40 km/h)
●VSC is activated
●The sensor cannot operate correctly because it is covered in some way.
●The windshield wipers are operating at high speed.
●The “ECT SNOW” switch is set to snow mode.
If vehicle-to-vehicle distance control driving is automatically canceled for any other
reason, there may be a malfunction in the system. Contact your Lexus dealer.
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Driving assist systems
To help enhance driving safety and performance, the following systems
operate automatically in response to various driving situations. Be aware,
however, that these systems are supplementary and should not be relied
upon too heavily when operating the vehicle.
■ ABS (Anti-lock Brake System)
Helps to prevent wheel lock when the brakes are applied suddenly, or if
the brakes are applied while driving on a slippery road surface.
■Brake assist
Generates an increased level of braking force after the brake pedal is
depressed, when the system detects a panic stop situation.
■VSC (Vehicle Stability Control)
Helps the driver to control skidding when swerving suddenly or turning on
slippery road surfaces.
■TRAC (Traction Control)
Maintains drive power and prevents the rear wheels (2WD models) or all
wheels (AWD models) from spinning wh en starting the vehicle or acceler-
ating on slippery roads.
■ Hill-start assist control (vehicles with an automatic transmission)
Prevents the vehicle from rolling backwards when starting on an incline or
slippery slope.
■EPS (Electric Power Steering)
Employs an electric motor to reduce the amount of effort needed to turn
the steering wheel.
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2-5. Driving information
08_IS350/250_U_(L/O_0808)
Dinghy towing (vehicles with a manual transmission)
Towing your vehicle with 4 wheels on the groundTo prevent damage to your vehicle, perform the following procedures
before towing. Shift the shift lever to neutral.
Switch to ACCESSORY mode. ( P. 1 2 8 )
Ensure that the audio system and other powered devices have been
turned off.
Release the parking brake.
After towing, leave the engine in idle for at least 3 minutes before driv-
ing the vehicle.
■Necessary equipment and accessories
Specialized equipment and accessories are required for dinghy towing. Contact
the service branch of the motor home manufacturer regarding recommended
equipment.
Your vehicle can be dinghy towed in a forward direction (with 4 wheels on
the ground) behind a motor home.
STEP1
STEP2
STEP3