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2-4. Using other driving systems
RX350/270_EE
■Automatic cancelation of constant speed control
The cruise control will stop maintaining the vehicle speed in the following situations:
●Actual vehicle speed is more than approximately 16 km/h (10 mph) below the
set vehicle speed.
At this time, the memorized set speed is not retained.
●Actual vehicle speed falls below approximately 40 km/h (25 mph).
●VSC is activated.
●VSC+ is activated (if equipped).
■Radar sensor and grille cover
Always keep the sensor and grille cover clean to ensure that the vehicle-to-vehicle
distance control operates properly. (Some obstructions, such as snow, ice and plas-
tic objects, cannot be detected by the obstruction sensor.)
Dynamic radar cruise control is canceled if an obstruction is detected.
■Warning lights, messages and buzzers for dynamic radar cruise control
Warning lights, messages and buzzers are used to indicate a system malfunction or
to inform the driver of the need for caution while driving. (→P. 5 5 7 ) Grille cover
Radar sensor
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2-4. Using other driving systems
RX350/270_EE
Pre-Crash Safety system∗
When the radar sensor detects the possibility of a frontal collision, the pre-
crash safety system such as the brakes and seat belts are automatically
engaged to lessen impact as well as vehicle damage.
■Pre-crash seat belts (front seat belts only)
If the pre-crash sensor detects that a collision is unavoidable, the pre-
crash safety 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. 9 0 )
However, the system will not operate in the event of skidding when the
VSC system is disabled.
■Pre-crash 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. The system may not warn the driver using a warning light,
warning display and buzzer when the system detects and judges braking
operations.
■Pre-crash braking
When there is a high 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-crash braking can be disabled
using the pre-crash braking off switch.
∗: If equipped
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2-4. Using other driving systems
RX350/270_EE
■Situations in which the pre-crash safety system does not function properly
The system may not function effectively in situations such as the following:
●On roads with sharp bends or uneven surfaces
●If a vehicle suddenly moves in front of your vehicle, such as at an intersection
●If a vehicle suddenly cuts in front of your vehicle, such as when overtaking
●In inclement weather such as heavy rain, fog, snow or sand storms
●When your vehicle is skidding with the VSC system off
●When an extreme change in vehicle height occurs
●When the axis of the radar is out of adjustment
■Automatic cancelation of the pre-crash safety system
When a malfunction occurs due to sensor contamination, etc. that results in the
sensors being unable to detect obstacles, the pre-crash safety system will be auto-
matically disabled. In this case, the system will not activate even if there is a collision
possibility.
■When there is a malfunction in the system, or if the system is temporarily unus-
able
Warning lights and/or warning messages will turn on or flash. (→P. 5 4 3 , 5 5 2 )
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4-3. Do-it-yourself maintenance
RX350/270_EEPress and hold the tire pressure
warning reset switch until the tire
pressure warning light blinks
slowly 3 times.
Wait for a few minutes in “ENGINE START STOP” switch to on,
and then turn the “ENGINE START STOP” switch off.
Registering ID codes
The tire pressure warning valve and transmitter is equipped with a unique
ID code. When replacing a tire pressure warning valve and transmitter, it
is necessary to register the ID code. Have the ID code registered by any
authorized Lexus dealer or repairer, or another duly qualified and
equipped professional.
STEP4
STEP5
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4-3. Do-it-yourself maintenance
4
Maintenance and care
RX350/270_EE
■When to replace your vehicle’s tires
Tires should be replaced if:
●You have tire damage such as cuts, splits, cracks deep enough to expose the
fabric, and bulges indicating internal damage
●A tire goes flat repeatedly or cannot be properly repaired due to the size or
location of a cut or other damage
If you are not sure, consult with any authorized Lexus dealer or repairer, or another
duly qualified and equipped professional.
■Replacing tires and wheels
If the ID code of the tire pressure warning valve and transmitter is not registered,
the tire pressure warning system will not work properly. After driving for about 10
minutes, the tire pressure warning light blinks for 1 minute and stays on to indicate a
system malfunction.
■Tire life
●Standard tire over 6 years old must be checked by a qualified technician even if
they have seldom or never been used or damage is not obvious.
●The compact spare tire could be deformed gradually in the long term even if
you don't use it. Be sure to have the compact spare tire checked by any autho-
rized Lexus dealer or repairer, or another duly qualified and equipped profes-
sional if it is over 5 years.
■Routine tire inflation pressure checks
The tire pressure warning system does not replace routine tire inflation pressure
checks. Make sure to check tire inflation pressure as part of your routine of daily
vehicle checks.
■If the tread on snow tires wears down 4 mm (0.16 in.)
The effectiveness of the tires as snow tires is lost
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4-3. Do-it-yourself maintenance
RX350/270_EE
■The initialization operation
●Make sure to carry out initialization after adjusting the tire inflation pressure.
Also, make sure the tires are cold before carrying out initialization or tire infla-
tion pressure adjustment.
●If you have accidentally turned the “ENGINE START STOP” switch off during
initialization, it is not necessary to press the reset switch again as initialization
will restart automatically when the “ENGINE START STOP” switch has been
turned to IGNITION ON mode for the next time.
●If you accidentally press the reset switch when initialization is not necessary,
adjust the tire inflation pressure to the specified level when the tires are cold,
and conduct initialization again.
■Warning performance of the tire pressure warning system
The warning of the tire pressure warning system will change in accordance with
driving conditions. For this reason, the system may give a warning even if the tire
pressure does not reach a low enough level, or if the pressure is higher than the
pressure that was adjusted to when the system was initialized.
■When initialization of the tire pressure warning system has failed
Initialization can be completed in a few minutes. However, in the following cases,
the settings have not been recorded and the system will not operate properly. If
repeated attempts to record tire inflation pressure settings are unsuccessful, have
the vehicle inspected by any authorized Lexus dealer or repairer, or another duly
qualified and equipped professional.
●When operating the tire pressure warning reset switch, the tire pressure warn-
ing light does not blink 3 times.
●After carrying out the initialization procedure, the tire pressure warning light
blinks for 1 minute then stays on after driving for 10 minutes.
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4-3. Do-it-yourself maintenance
4
Maintenance and care
RX350/270_EE
CAUTION
■When inspecting or replacing tires
Observe the following precautions to prevent accidents.
Failure to do so may cause damage to parts of the drive train, as well as dangerous
handling characteristics, which may lead to an accident resulting in death or serious
injury.
●Do not mix tires of different makes, models or tread patterns.
Also, do not mix tires of remarkably different treadwear.
●Do not use tire sizes other than those recommended by Lexus.
●Do not mix differently constructed tires (radial, bias-belted or bias-ply tires).
●Do not mix summer, all season and snow tires.
●Do not use tires that have been used on another vehicle.
Do not use tires if you do not know how they were used previously.
●Do not tow if your vehicle has a compact spare tire installed.
■When initializing the tire pressure warning system
Do not push the tire pressure warning reset switch without first adjusting the tire
inflation pressure to the specified level. Otherwise, the tire pressure warning light
may not come on even if the tire inflation pressure is low, or it may come on when
the tire inflation pressure is actually normal.
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4-3. Do-it-yourself maintenance
4
Maintenance and care
RX350/270_EE
7ECU-IG1 NO. 110 A
Multiplex communication system,
steering sensor, shift lock control sys-
tem, tilt and telescopic steering, auto-
matic transmission system, power
back door, pre-crash safety system,
vehicle stability control system, tire
pressure warning system
8S/ROOF30 AMoon roof
9FUEL OPN7. 5 AFuel filler door opener
10PSB30 APre-crash seat belt
11TI & TE30 ATilt and telescopic steering system
12DR LOCK10 ADR LOCK
13FR FOG7. 5 AFront fog lights
14P- S E AT L H30 APower seat (left-side)
154WD7. 5 AAW D s y s t e m
16INVERTER20 A
17RR FOG7. 5 ARear fog lights
18D/L ALT B25 A
Multiplex communication system,
power door lock system, power back
door
19EPS10 AElectric power steering system
20ECU-IG1 NO. 210 ALexus parking assist-sensor, AWD
system, pre-crash seat belt
FuseAmpereCircuit
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