2011 Lexus GS350 brake sensor

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2-4. Using other driving systems
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When driving
GS_G_U (OM30C11U)
October 28, 2011 5:15 pm
Cruising in vehicle-to-vehicle distance control mode
This mode employs a radar sensor to detect the presence of vehicles
within 400 ft. (120 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
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 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.

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2-4. Using other driving systems
GS_G_U (OM30C11U)
October 28, 2011 5:15 pm
CAUTION
■Before using dynamic radar cruise control
Do not overly rely on vehicle-to-vehicle distance control.
Be aware of the set vehicle speed. If automatic deceleration/acceleration is not
appropriate, adjust the vehicle speed, as well as the distance between your vehicle
and vehicles ahead by applying the brakes, etc.
■To avoid operating the dynamic radar cruise control by mistake
Keep the “ON-OFF” button off when not in use.
■Situations unsuitable for dynamic radar cruise control
Do not use dynamic radar cruise control in any of the following situations.
Doing so may result in inappropriate control of speed and could cause serious or
fatal accident.
●In heavy traffic
●On roads with sharp bends
●On winding roads
●On slippery roads, such as those covered with rain, ice or snow
●On steep downhills, where there are sudden changes between sharp up and
down gradients
Vehicle speed may exceed the set speed when driving down a steep hill.
●At entrances to expressways
●When weather conditions are bad enough that they may prevent the sensors
from functioning correctly (fog, snow, sandstorm, etc.)
●When the approach warning buzzer can be heard often
●When emergency towing

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2-4. Using other driving systems
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When driving
GS_G_U (OM30C11U)
October 28, 2011 5:15 pm
CAUTION
■When the radar sensor may not be correctly detecting the vehicle ahead
Apply the brakes as necessary when any of the following types of vehicles are in
front of you.
As the sensor may not be able to correctly detect these types of vehicles, the prox-
imity alarm ( →P. 552) will not be activated, and a serious or fatal accident may
result.
●Vehicles that cut in suddenly
●Vehicles traveling at low speeds
●Vehicles that are not moving
●Vehicles with small rear ends (trailers with no load on board etc.)
●Motorcycles traveling in the same lane
■Conditions under which the vehicle-to-vehicle distance control may not function
correctly
Apply the brakes as necessary in the following conditions as the radar sensor may
not be able to correctly detect vehicles ahead, and a serious or fatal accident may
result.
●When water or snow thrown up by the surrounding vehicles hinders the function-
ing of the sensor
●When your vehicle is pointing upwards (caused by a heavy load in the trunk, etc.)
●When the road curves or when the lanes are narrow
●When steering wheel operation or your position in the lane is unstable
●When the vehicle ahead of you decelerates suddenly

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2-4. Using other driving systems
GS_G_U (OM30C11U)
October 28, 2011 5:15 pm
■The intuitive parking assist can be operated when
The “ENGINE START STOP” switch is in the IGNITION ON mode.
■When the system malfunctions
●If a malfunction occurs and no obstacles have been detected, a warning is dis-
played, and a malfunction beep sounds for 7 seconds.
If an obstacle has been detected, or another malfunction occurs in a different
sensor, the malfunction beeps will not sound.
●In the following circumstances the displayed warning will disappear:
• If you switch the screen to a different mode.
• If you turn off the intuitive parking assist main switch.
• If the vehicle speed exceeds 6 mph (10 km/h). Once the vehicle speed dropsbelow 6 mph (10 km/h), the warning will be displayed again.
●If the malfunction screen is displayed, the detection range of the dual sensors is
shortened. In this case, the necessity for obstacle evasion (whether the obstacle
will come within 0.8 ft. [25 cm] of the vehicle or not) will not be calculated.
■When using the intuitive parking assist
●The sensors’ detection areas and reaction times are limited. When moving for-
ward or reversing, check the areas surrounding the vehicle (especially the sides
of the vehicle) for safety, and drive slowly, using the brake to control the vehicle’s
speed.
• The sensors’ detection areas are limited to the areas around the vehicle’s frontand rear bumpers.
• Depending on the shape of the obstacle and other factors, the detection dis-
tance may shorten, or detection may be impossible.
• There will be a short delay between obstacle detection and display. Even at slow speeds, there is a possibility that the obstacle will come within 0.8 ft. (25
cm) of the vehicle before the display is shown and the warning beep sounds.
• Braking distance may differ according to the road conditions (rain, gravel etc.).
• It might be difficult to hear beeps due to the volume of audio system or air flow noise of air conditioning system.
• For long obstacles such as walls, the obstacle warning may change as the obstacle gets closer.

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2-4. Using other driving systems
GS_G_U (OM30C11U)
October 28, 2011 5:15 pm
PCS (Pre-Collision System)∗
∗: If equipped
When the radar sensor detects possibility of a frontal collision. Pre-colli-
sion systems such as the brakes and seat belts are automatically engaged
to lessen impact and injuries to occupants as well as vehicle damage.
■ Pre-collision seat belts (front seats only)
If the pre-collision sensor detects that a collision is unavoidable, the pre-
collision system will retract the seat belt before the collision occurs.
The same will happen if the driver makes an emergency braking or loses
control of the vehicle. ( →P. 6 5 )
However, the system will not operate in the event of skidding when the
TRAC/VSC systems are disabled.
■ Pre-collision brake assist
When there is a high possibility of a frontal collision, the system applies
greater braking force in relation to how strongly the brake pedal is
depressed.
■Pre-collision braking
When there is a possibility of a frontal collision, the system warns the driver
using a warning light, warning display and buzzer. If the system determines
that a collision is unavoidable, the brakes are automatically applied to
reduce the collision speed. Pre-collision braking can be disabled using the
pre-collision braking off switch.
■AVS (if equipped)
If the system determines that the collision is unavoidable, the operation of
AV S ( →P. 198) helps prevent the vehicle front from going down when
hard brakes are applied.

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2-4. Using other driving systems
GS_G_U (OM30C11U)
October 28, 2011 5:15 pm
■Obstacles not detected
The sensor cannot detect plastic obstacles such as pylons. There may also be occa-
sions when the radar sensor cannot detect pedestrians, animals, bicycles, motorcy-
cles, trees, or snowdrifts.
■The pre-collision system is operational when
●Pre-collision seat belts (linked to the radar sensor)
• Vehicle speed is above 4 mph (5 km/h).
• The speed at which your vehicle is approaching the obstacle or oncomingvehicle exceeds 19 mph (30 km/h).
• The front occupants are wearing a seat belt.
●Pre-collision seat belts (linked to brake operation)
• Vehicle speed exceeds 19 mph (30 km/h).
• The system detects sudden braking or skidding.
• The front occupants are wearing a seat belt.
●Pre-collision brake assist
• Vehicle speed is above 19 mph (30 km/h).
• The speed at which your vehicle is approaching the obstacle or oncoming vehicle exceeds 19 mph (30 km/h).
• The brake pedal is depressed.
●Pre-collision braking
• The pre-collision braking off button is not pressed.
• Vehicle speed is greater than about 10 mph (15 km/h).
• The speed at which your vehicle is approaching the obstacle or the vehicle running ahead of you is greater than about 10 mph (15 km/h).
●AVS (if equipped)
• Vehicle speed is above 4 mph (5 km/h).
• The speed at which your vehicle is approaching the obstacle or oncomingvehicle exceeds 19 mph (30 km/h).

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2-4. Using other driving systems
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When driving
GS_G_U (OM30C11U)
October 28, 2011 5:15 pm
■Conditions that may trigger the system even if there is no possibility of collision
●When there is an object by the roadside at the entrance to a curve
●When passing an oncoming vehicle on a curve
●When driving over a narrow iron bridge
●When there is a metal object on the road surface
●When driving on an uneven road surface
●When passing an oncoming vehicle on a left-turn
●When your vehicle rapidly closes on the vehicle in front
●When a grade separation/interchange, sign, billboard, or other structure
appears to be directly in the vehicle’s line of travel
●When an extreme change in vehicle height occurs
●When there is an abnormality in the radar sensor
●When climbing a steep hill causes an overhead billboard or other metallic struc-
ture to appear directly in the vehicle’s line of travel
●When passing through certain ETC (Electronic Toll Collection system) gates
When the system is activated in the situations described above there is also a possi-
bility that the seat belts will retract quickly and the brakes will be applied with a force
greater than normal. When the seat belt is locked in the retracted position, stop the
vehicle in a safe place, release the seat belt and refasten.
■When there is a malfunction in the system
Warning lights and/or warning messages will turn on or flash. ( →P. 535, 546)

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4-3. Do-it-yourself maintenance
GS_G_U (OM30C11U)
October 28, 2011 5:15 pm
FuseAmpereCircuit
8MPX-B10
Multiplex communication system,
front controller, door control system
(power door lock system, door cour-
tesy lights, power windows, power
rear view mirror control system, out-
side rear view mirror heaters), power
seat system, steering sensors, elec-
tronically controlled brake system, tilt
and telescopic steering wheel,
gauges and meters, combination
switch
9DOME10
Foot lights, vanity lights, gauges and
meters, steering spot light, steering
switch illumination, rear personal
lights, automatic transmission selec-
tor lever spot light, front personal
lights
10CDS10Noise filter
11ABS MAIN210Electronically controlled
brake system
12ABS MOTOR30ABS
13ABS MAIN110Capacitor
14E/G-B60FR CTRL BATT, ETCS, ALT-S,
A/F HTR and INJ2
15P/ I - B60EFI NO.1, F/PMP and INJ
16ABS150VDIM
17RH J/B-B30AM2, DOOR FR and DOOR RR