2018 LEXUS RX450h stop start

256 4-2. Driving procedures
RX450h_RX450hL _U_OM48F85UTurns the brake hold system on The brake hold standby indicator
(green) comes on. Wh ile the system is
holding the brakes, the brake hold oper-
ated indicator (yellow) will illuminate. ■
Brake hold system operating conditions
The brake hold system cannot be turn ed on in the following conditions:●
The driver’s door is not closed. ●
The driver’s seat seat belt is not buckled.
If either of the conditions above are detected when the brake hold system is enabled, the
system will turn off and the brake hold standby in dicator light will go off. In addition, if any
of the conditions are detected while the sy stem is holding the brakes, a warning buzzer
will sound and a message will be shown on th e multi-information di splay. The parking
brake will then be set automatically. ■
Brake hold function ●
If the brake pedal is left released for a pe riod of about 3 minutes after the system has
started holding the brakes, the parking brake will be set automatically. In this case, a
warning buzzer sounds and a message is shown on the multi- informatio n display.●
To turn the system off while the system is holding the brakes, firmly depress the brake
pedal and press the switch again. ●
The brake hold function may not hold the vehicle when the vehicle is on a steep incline.
In this situation, it may be necessary for the driver to apply the brakes. A warning
buzzer will sound and the mult i-information display will info rm the driver of this situa-
tion. If a warning message is shown on the multi-information display, read the message
and follow the instructions.Brake Hold The brake hold system keeps the brake appl ied when the shift lever is in D, S or
N with the system on and the brake peda l has been depressed to stop the vehi-
cle. The system releases the brake wh en the accelerator pedal is depressed
with the shift lever in D or S to allow smooth start off.

3094-5. Using the driving support systems
4
Driving
RX450h_RX450hL _U_OM48F85UThis mode employs a radar sensor to detect the presence of vehicles up to
approximately 328 ft. (100 m) ahead, de termines the current vehicle-to-vehicle
following distance, and operates to main tain a suitable following distance from
the vehicle ahead. Note that vehicle-to-vehicle distance will cl ose in when traveling on downhill slopes.
Example of constant speed cruising
When there are no vehicles ahead The vehicle travels at the speed set by the driver. The desired vehicle-to-vehicle dis-
tance can also be set by operating the vehicle-to-vehicle distance switch.
Example of deceleration cruising and follow-up cruising
When a preceding vehicle driving sl ower than the set speed appearsWhen a vehicle is detected running ahead of you, the system automatically deceler-
ates your vehicle. When a greater reduction in vehicle speed is necessary, the system
applies the brakes (the stop lights will come on at this time). Th e system will respond to
changes in the speed of the vehicle ahead in order to maintain the vehicle-to-vehicle
distance set by the driver. Approach warning warns you when the system cannot
decelerate sufficie ntly to prevent your vehicle from closing in on the vehicle ahead.
When the vehicle ahead of you stops, your vehicle will also stop (vehicle is stopped by
system control). After the vehicle ahead starts off, pushing the cruise control lever up
or depressing the accelerator pedal will resume follow-up cruising.
Example of acceleration
When there are no longer any preceding vehicles driving slower than the set
speed The system accelerates until the set speed is reached. The system then returns to con-
stant speed cruising.Driving in vehicle-to-vehicle distance control mode
1
2
3

3134-5. Using the driving support systems
4
Driving
RX450h_RX450hL _U_OM48F85UAfter the vehicle ahead of you starts off,
push the lever up.
Your vehicle will also resume follow-up
cruising if the accelerator pedal is
depressed after the vehicle ahead of
you starts off.
Pulling the lever toward you cancels
the speed control. The speed control is also canceled when
the brake pedal is depressed.
(When the vehicle has been stopped by
system control, depressing the brake
pedal does not cancel the setting.)
Pushing the lever up resumes the
cruise control and returns vehicle
speed to the set speed. However, when a vehicle ahead is not detected, cruise control does not resume when
the vehicle speed is approximately 25 mph (40 km/h) or less.Resuming follow-up cruising when the vehicle has been stopped by sys-
tem control (vehicle-to-vehicle distance control mode)
Canceling and resuming the speed control 1
2

316 4-5. Using the driving support systems
RX450h_RX450hL _U_OM48F85U■
Dynamic radar cruise control with full-speed range can be set when ●
The shift lever is in D or range 4 or higher of S has been selected.●
Range 4 or higher has been selected by using the paddle shift switch.
(vehicles with padd le shift switches)●
Vehicle speed is at or abov e approximately 30 mph (50 km/h). However, when a pre-
ceding vehicle is detected, the dynamic ra dar cruise control with full-speed range can
be set even if the vehicle speed is below approximately 30 mph (50 km/h).■
Accelerating after setting the vehicle speed
The vehicle can accelerate by operating the accelerator pedal. After accelerating, the
set speed resumes. However, during vehicle-to-vehicle distance control mode, the vehi-
cle speed may decrease below the set speed in order to maintain the distance to the pre-
ceding vehicle. ■
When the vehicle stops while follow-up cruising ●
Pushing the lever up while the vehicle ahead stops will resume follow-up cruising if the
vehicle ahead starts off within approximat ely 3 seconds after the switch is pressed.●
If the vehicle ahead starts off within 3 seco nds after your vehicle stops, follow-up cruis-
ing will be resumed. ■
Automatic cancelation of vehicle- to-vehicle distance control mode
Vehicle-to-vehicle distance control mode is automatically canceled in the following situ-
ations. ●
Actual vehicle speed falls below approximately 25 mph (40 km/h) when there are no
vehicles ahead. ●
The preceding vehicle leaves the lane when yo ur vehicle is following at a vehicle speed
at or below approximately 25 mph (40 km/h ). Otherwise, the sensor cannot properly
detect the vehicle. (“Radar Cruise Contro l Not Available No Preceding Vehicles” is
displayed on the multi-information display) ●
VSC is activated. ●
TRAC is activated for a period of time. ●
When the VSC or TRAC system is turned off. ●
The sensor cannot detect correctly because it is covered in some way. ●
Pre-collision braking is activated. ●
The parking brake is operated. ●
The vehicle is stopped by system control on a steep incline. ●
The following are detected when the vehicle has been stopped by system control:
• The driver is not wearing a seat belt.
• The driver’s door is opened.
• The vehicle has been stopped for about 3 minutes
If vehicle-to-vehicle distance control mode is automatically canceled for any other rea-
son, there may be a malfunction in th e system. Contact your Lexus dealer.

326 4-5. Using the driving support systems
RX450h_RX450hL _U_OM48F85U■
Conditions under which the BSM function may not function correctly ●
The BSM function may not detect vehicles correctly in the following situations:
• When the sensor is misaligned due to a stro ng impact to the sensor or its surround-
ing area
• When mud, snow, ice, a sticke r, etc. is covering the sensor or surrounding area on
the rear bumper
• When driving on a road surf ace that is wet with standi ng water during bad weather,
such as heavy rain, snow, or fog
• When multiple vehicles are approaching wi th only a small gap between each vehicle
• When the distance between your vehicle and a following vehicle is short
• When there is a significant difference in speed between your vehicle and the vehicle
that enters the detection area
• When the difference in speed between your vehicle and another vehicle is changing
• When a vehicle enters a detection area traveling at about the same speed as your
vehicle
• As your vehicle starts from a stop, a vehicle remains in the detection area
• When driving up and down cons ecutive steep inclines, such as hills, dips on the road,
etc.
• When driving on roads with sharp bends, consecutive curves, or uneven surfaces
• When vehicle lanes are wide, or when driving on the edge of a lane, and the vehicle
in an adjacent lane is far away from your vehicle
• When towing a trailer (vehicles with towing package)
• When items such as a bicycle carrier are installed on the rear of the vehicle
• When there is a significant difference in height between your vehicle and the vehicle
that enters the detection area
• Immediately after the BSM function is turned on ●
Instances of the BSM function unnecessarily detecting a vehicle and/or object may
increase in the following situations:
• When the sensor is misaligned due to a stro ng impact to the sensor or its surround-
ing area
• When the distance between your vehicle and a guardrail, wall, etc. that enters the
detection area is short
• When driving up and down cons ecutive steep inclines, such as hills, dips on the road,
etc.
• When vehicle lanes are narrow, or when driv ing on the edge of a lane, and a vehicle
traveling in a lane other than the ad jacent lanes enters the detection area
• When driving on roads with sharp bends, consecutive curves, or uneven surfaces
• When the tires are slipping or spinning
• When the distance between your vehicle and a following vehicle is short
• When a bicycle carrier or other accessory is installed to the rear of the vehicle
• When towing a trailer (vehicles with towing package)

3494-5. Using the driving support systems
4
Driving
RX450h_RX450hL _U_OM48F85U■
The Intelligent Clearance Sonar function will operate when
The function will operate when the ICS OFF indicator is not illuminated or flashing ( → P.
345, 353) and all of the fo llowing conditions are met:●
Hybrid system output restriction control
• The Intelligent Clearance Sonar system is enabled.
• The vehicle speed is 10 mph (15 km/h) or less.
• There is a stationary object in the traveling direction of the vehicle and 6 to 13 ft. (2
to 4 m) away.
• The system determines that a stronger-t han-normal brake operation is necessary to
avoid a collision. ●
Brake control
• Hybrid system output restri ction control is operating.
• The system determines that an emergenc y brake operation is necessary to avoid a
collision.■
The Intelligent Clearance Sonar fu nction will stop operating when
The function will stop operating if an y of the following conditions are met:●
Hybrid system output restriction control
• The Intelligent Clearance Son ar system is disabled.
• The collision becomes avoidable with normal brake operation.
• The stationary object is no lo nger 6 to 13 ft. (2 to 4 m) away in the traveling direction
of the vehicle. ●
Brake control
• The Intelligent Clearance Son ar system is disabled.
• Approximately 2 seconds elapse after the vehicle is stopped by brake control.
• The brake pedal is depressed after the vehicle is stopped by brake control.
• The stationary object is no lo nger 6 to 13 ft. (2 to 4 m) away in the traveling direction
of the vehicle.■
Detection range of the Intellig ent Clearance Sonar function
The detection range of the Intelligent Cleara nce Sonar function differs from the detec-
tion range of the intu itive parking assist. ( → P. 337)
Therefore, even if the intuit ive parking assist detects an object and provides a warning,
the Intelligent Clearance Sonar function may not start operating. ■
If the Intelligent Clearance Sonar function has operated
If the vehicle is stopped due to operation of the Intelligent Clearance Sonar function, the
Intelligent Clearance Sonar system will be di sabled and the ICS OFF indicator will illumi-
nate.

358 4-5. Using the driving support systems
RX450h_RX450hL _U_OM48F85U■
The Rear Cross Traffic Auto Brake function will operate when
The function will operate when the ICS OFF indicator is not illuminated or flashing ( → P.
345, 353) and all of the fo llowing conditions are met:●
Hybrid system output restriction control
• The Intelligent Clearance Son ar with Rear Cross Traffi c Auto Brake is enabled.
• The vehicle speed is 10 mph (15 km/h) or less.
• The shift lever is in R.
• The system determines that a stronger than normal brake operation is necessary to
avoid a collision with an approaching vehicle. ●
Brake control
• Hybrid system output restri ction control is operating.
• The system determines that an emergenc y brake operation is necessary to avoid a
collision with an approaching vehicle.■
The Rear Cross Traffic Auto Brake function will stop operating when
The function will stop operating if an y of the following conditions are met:●
Hybrid system output restriction control
• The Intelligent Clearance Sonar with Rear Cross Traffic Auto Brake is disabled.
• The collision becomes avoidable with normal brake operation.
• A vehicle is no longer approaching from th e right or left at the rear of the vehicle.●
Brake control
• The Intelligent Clearance Sonar with Rear Cross Traffic Auto Brake is disabled.
• Approximately 2 seconds elapse after the vehicle is stopped by brake control.
• The brake pedal is depressed after the vehicle is stopped by brake control.
• A vehicle is no longer approaching from th e right or left at the rear of the vehicle.■
Detection area of the Rear Cross Traffic Auto Brake function
The detection area of the Rear Cross Traffic Auto Brake function differs from the detec-
tion area of the RCTA function. ( → P. 329)
Therefore, even if the RCTA function detect s a vehicle and provides an alert, the Rear
Cross Traffic Auto Brake function may not start operating. ■
If the Rear Cross Traffic Auto Brake function has operated
If the vehicle is stopped due to operation of the Rear Cross Traffic Auto Brake function,
the Rear Cross Traffic Auto Brake function will be disabled and the ICS OFF indicator
will illuminate.

382 4-5. Using the driving support systems
RX450h_RX450hL _U_OM48F85U◆ ECB (Electronically Controlled Brake System)
The electronically controlled system generates braking force corresponding
to the brake operation
◆ ABS (Anti-lock Brake System)
Helps to prevent wheel lock when the br akes are applied suddenly, or if the
brakes are applied while drivin g on a slippery road surface
◆ Brake assist
Generates an increased level of br aking force after the brake pedal is
depressed when the system detects a panic stop situation
◆ VSC (Vehicle Stability Control)
Helps the driver to contro l skidding when swerving suddenly or turning on
slippery road surfaces.
◆ Enhanced VSC (Enhanced Vehicle Stability Control)
Provides cooperative control of the ABS, TRAC, VSC and EPS.
Helps to maintain directional stability when swerving on slippery road sur-
faces by controlling steering performance.
◆ Trailer Sway Control (if equipped)
Helps the driver to control trailer sway by selectively applying brake pressure
for individual wheels and reducing dr iving torque when trailer sway is
detected.
◆ TRAC (Traction Control)
Helps to maintain drive power and pr event the drive wheels from spinning
when starting the vehicle or accelerating on slippery roads
◆ Hill-start assist control
Helps to reduce the backward movement of the vehicle when starting on an
uphillDriving assist systems To keep driving safety and performance, the following systems operate auto-
matically in response to various drivin g situations. Be aware, however, that
these systems are supplementary and shou ld not be relied upon too heavily
when operating the vehicle.