stop start LEXUS RX450H 2020 Service Manual

5156-2. Using the air conditioning system and defogger
6
Interior features
RX350/RX350L_U
■Registering air conditioning settings to electronic keys (vehicles with driving position
memory)
●Unlocking the vehicle using an electronic ke y and turning the engine switch to IGNI-
TION ON mode will recall that key’s re gistered air conditioning settings.
●When the engine switch is turned off, the current air conditioning settings will automat-
ically be registered to the electronic key that was used to unlock the vehicle.
●The system may not operate correctly if more th an one electronic key is in the vicinity or
if the smart access system with push-button start is used to unlock a passenger door.
●The doors that can recall the air conditioning setting when unlocked using the smart
access system with push-button start can be changed.* For details, contact your Lexus
dealer.
*: The doors that can recall the driving positi on memory are changed at the same time.
■Using automatic mode
Fan speed is adjusted automatically according to the temperature setting and the ambi-
ent conditions.
Therefore, the fan may stop for a while until wa rm or cool air is ready to flow immediately
after the “AUTO” button is pressed or “AUTO” is selected.
■How the system judges if a passenger is in the vehicle when in S-FLOW mode
In S-FLOW mode, the system judges if a passenger is in the vehicle as follows:
• Front passenger seat: A passeng er is judged to be in the front passenger seat when the
system detects an object on the front passenger seat, fastening of the front passenger
seat belt, changing of the set temperature for the front passenger seat or the opening
and closing of the front passenger door. (However, when only opening and closing of
the front passenger door is detected, the sy stem will judge that a passenger is not in
the front passenger seat after the vehicl e speed reaches approximately 12 mph (20
km/h) or more.)
• Rear seats (automatic S-FLOW mode only): A passenger is judged to be in a rear seat when the system detects the opening and closin g of a rear door or the operation of the
rear air conditioning system (RX350L).
If a passenger is judged to be in the vehicl e, the system will retain the judgement for a
certain amount of time after th e engine switch is turned off.
■Operation of automatic S-FLOW mode
When the system is operating in automati c S-FLOW mode, if the system detects the
opening and closing of a rear door or the op eration of the rear air conditioning system
(RX350L), S-FLOW mode will be disabled . To enable S-FLOW mode, select on
the option control screen. (I n this case, the system will operate in manual S-FLOW
mode.)
■Changing from manual S-FLOW mode to automatic S-FLOW mode
Select on the option control screen to disable S-FLOW mode.
Turn the engine switch off.
Wait for 60 minutes or more and change the engine switch to IGNITION ON mode.
■Using the voice command system (vehicles with a navigation system)
Air conditioning system can be operated using voice commands. For details, refer to the
“NAVIGATION SYSTEM OWNER’S MANUAL”.
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5456-5. Using the other interior features
6
Interior features
RX350/RX350L_U
■Name for all partsPower supply switch
Operation indicator light
Charge area
■Using the wireless chargerPress the power supply switch of
the wireless charger.
Pressing the switch again turns the
wireless charger off.
When turned on, the operation indi-
cator light (green) comes on.
When the engine switch is turned off,
the on/off state of the wireless char-
ger will be memorized.
Place a portable device on the
charging area with its charging
surface facing down.
While charging, the operation indi-
cator light (orange) will be illumi-
nated.
If charging does not begin, move the
portable device as close to the cen-
ter of the charging area as possible.
When charging is complete, the operatio n indicator light (green) will illuminate.
●Recharging function
• If a certain amount of time has elapsed since charging completed and the portable device has not been moved, the wireless charger will
restart charging.
• If the portable device is moved with in the charging area, charging will
stop temporarily then restart.
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643
8When trouble arises
RX350/RX350L_U
8-1. Essential informationEmergency flashers .................. 644
If your vehicle has to be stopped in
an emergency .......................... 645
8-2. Steps to take in an emergency
If your vehicle needs to be towed................................ 646
If you think something is wrong ........................................... 652
Fuel pump shut off system .......................................... 653
If a warning light turns on or a warning buzzer
sounds.......................................... 654
If a warning message is displayed...................................... 661
If you have a flat tire .................. 666
If the engine will not start ........ 682
If the electronic key does not operate properly .............684
If the vehicle battery is discharged ................................. 687
If your vehicle overheats ......... 692
If the vehicle becomes stuck ............................................. 695

6538-2. Steps to take in an emergency
8
When trouble arises
RX350/RX350L_U
Follow the procedure below to restart the engine after the system is activated.Turn the engine switch to ACCESSORY mode or turn it off.
Restart the engine.
Fuel pump shut off system
To minimize the risk of fuel leakage when the engine stalls or when an airbag
inflates upon collision, the fuel pump shut off system stops the supply of fuel to
the engine.
NOTICE
■Before starting the engine
Inspect the ground under the vehicle.
If you find that fuel has leaked onto the ground, the fuel system has been damaged and
is in need of repair. Do not restart the engine.
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6608-2. Steps to take in an emergency
RX350/RX350L_U
WARNING
■Maintenance of the tires
Each tire, including the spare (if provided), should be checked monthly when cold and
inflated to the inflation pressure recomm ended by the vehicle manufacturer on the
vehicle placard or tire inflation pressure label (tire and load information label). (If your
vehicle has tires of a different size than the size indicated on the vehicle placard or tire
inflation pressure label [tire and load in formation label], you should determine the
proper tire inflation pressure for those tires.)
As an added safety feature, your vehicle ha s been equipped with a tire pressure moni-
toring system (TPMS-tire pressure warning system) that illuminates a low tire pressure
telltale (tire pressure warning light) when on e or more of your tires is significantly
under-inflated. Accordingly, when the low ti re pressure telltale (tire pressure warning
light) illuminates, you should stop and check your tires as soon as possible, and inflate
them to the proper pressure. Driving on a si gnificantly under-inflated tire causes the
tire to overheat and can lead to tire failure . Under-inflation also reduces fuel efficiency
and tire tread life, and may affect the vehicle’s handling and stopping ability.
Please note that the TPMS (tire pressure wa rning system) is not a substitute for proper
tire maintenance, and it is th e driver’s responsibility to ma intain correct tire pressure,
even if under-inflation has not reached the le vel to trigger illumination of the TPMS low
tire pressure telltale (tir e pressure warning light).
Your vehicle has also been equipped with a TPMS (tire pressure warning system) mal-
function indicator to indicate when the system is not operating properly. The TPMS
(tire pressure warning system) malfunction indi cator is combined with the low tire pres-
sure telltale (tire pressure warning light). When the system detects a malfunction, the
telltale will flash for approximately one mi nute and then remain continuously illumi-
nated. This sequence will cont inue upon subsequent vehicle start-ups as long as the
malfunction exists. When the malfunction in dicator is illuminated, the system may not
be able to detect or signal low tire pressure as intended.
TPMS (tire pressure warning system) malfun ctions may occur for a variety of reasons,
including the installation of replacement or alternate tires or wheels on the vehicle that
prevent the TPMS (tire pressure warning system) from functioning properly. Always
check the TPMS (tire pressure warning system) malfunction telltale after replacing one
or more tires or wheels on your vehicle to ensure that the replacement or alternate
tires and wheels allow the TPMS (tire pressu re warning system) to continue to function
properly.
NOTICE
■To ensure the tire pressure warning system operates properly
Do not install tires with different specifications or makers, as the tire pressure warning
system may not operate properly.

6638-2. Steps to take in an emergency
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When trouble arises
RX350/RX350L_U
Take the appropriate actions as instructed in the message displayed.
If any of the following messages are displa yed, also refer to this Owner’s Manual.
■If “Shift to P Before Exiting Vehicle” is shown
Message is displayed when the driver’s door is opened without turning the
engine switch off with the shift le ver in any position other than P.
Shift the shift lever to P.
■If “Power Turned Off to Save Battery” is displayed
This message is displayed when the power was cut off due to the automatic
power off function.
The next time the engine is started, increase the engine speed slightly and
maintain it at that speed for approximately 5 minutes to recharge the battery.
■If “AWD System Overheated Switching to 2WD Mode” or “AWD System
Overheated 2WD Mode Engaged” is displayed (AWD models)
This message may be displayed when driving under extremely high load con-
ditions.
Drive the vehicle at low speeds or stop the vehicle in a safe place with the
engine running until the message is cleared.
If the message is not cleared, have the vehicle inspected by your Lexus dealer.
■If “A New Key has been Registered Contact Your Dealer for Details” is dis-
played
This message will be displayed each time the driver’s door is opened when the
doors are unlocked from the outside fo r approximately one week after a new
electronic key has been registered.
If this message is displayed but you ha ve not had a new electronic key regis-
tered, ask your Lexus dealer to check if an unknown electronic key (other than
those in your possession) has been registered.
■When “Headlight System Malfunction Visit Your Dealer” is displayed
The following systems may be malfunct ioning. Have the vehicle inspected by
your Lexus dealer immediately.
●The LED headlight system
●The automatic headlight leveling system
●Automatic High Beam
●AFS (Adaptive Front-lighting System) (if equipped)
Other messages displayed on the multi-information display

6868-2. Steps to take in an emergency
RX350/RX350L_U
■Stopping the engine
Shift the shift lever to P, set the parking brake, and press the engine switch as you nor-
mally do when stopping the engine.
■Replacing the key battery
As the above procedure is a temporary measure, it is recommended that the electronic
key battery be replaced immediately when the battery is depleted. ( P. 623)
■Changing engine switch modes
Release the brake pedal and press the engine switch in step above.
The engine does not start and modes will be changed each time the switch is pressed.
(  P. 232)
■When the electronic key does not work properly
●Make sure that the smart access system wi th push-button start has not been deacti-
vated in the customization setting. If it is off, turn the function on.
(Customizable features P. 722)
●Check if battery-saving mode is set. If it is set, cancel the function. (P. 148)
WARNING
■When using the mechanical key and operating the power windows or the moon roof
or panoramic moon roof
Operate the power window or the moon roof or panoramic moon roof after checking
to make sure that there is no possibility of any passenger having any of their body parts
caught in the window or the moon roof or panoramic moon roof.
Also, do not allow children to op erate the mechanical key. It is possible for children and
other passengers to get caught in the powe r window or the moon roof or panoramic
moon roof.
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6938-2. Steps to take in an emergency
8
When trouble arises
RX350/RX350L_U
Add coolant if necessary.
Water can be used in an emergency if
coolant is unavailable.
Start the engine and turn the air conditioning system on to check that the radi-
ator cooling fans operate and to check for coolant leaks from the radiator or
hoses.
The fans operate when the air conditioning system is turned on immediately after a
cold start. Confirm that the fans are operating by checking the fan sound and air flow.
If it is difficult to check these, turn the air conditioning system on and off repeatedly.
(The fans may not operate in freezing temperatures.)
If the fans are not operating:
Stop the engine immediately an d contact your Lexus dealer.
If the fans are operating:
Have the vehicle inspected at the nearest Lexus dealer.
Check if “Engine Coolant Temp High St op in a Safe Place See Owner’s Man-
ual” is shown on the multi-information display.
If the message does not disappear:
Stop the engine and contact your Lexus dealer.
If the message is not displayed:
Have the vehicle inspected at the nearest Lexus dealer.
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6958-2. Steps to take in an emergency
8
When trouble arises
RX350/RX350L_U
Stop the engine. Shift the shift lever to P and set the parking brake.
Remove the mud, snow or sand from around the front wheels.
Place wood, stones or some other material under the front wheels to help pro-
vide traction.
Restart the engine.
AWD models: Activate all-wheel drive lock mode. ( P. 377)
Shift the shift lever to D or R and rele ase the parking brake. Then, while exer-
cising caution, depress the accelerator pedal.
■When it is difficult to free the vehicle
If the vehicle becomes stuck
Carry out the following procedures if the tires spin or the vehicle becomes
stuck in mud, dirt or snow:
Press to turn off TRAC.
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753What to do if... (Troubleshooting)
RX350/RX350L_U
●Did you press the engine switch while firmly depressing the brake pedal?
( P. 231)
●Is the shift lever in P? ( P. 233)
●Is the electronic key anywhere detectable inside the vehicle? ( P. 146)
●Is the steering wheel unlocked? ( P. 233)
●Is the electronic key battery weak or depleted?
In this case, the engine can be started in a temporary way. (P. 685)
●Is the battery discharged? ( P. 687)
●Is the engine switch in IGNITION ON mode?
If you cannot release the shift lever by depressing the brake pedal with the
engine switch in IGNITION ON mode ( P. 239, 244)
●It is locked automatically to prevent theft of the vehicle. ( P. 233)
●Is the window lock switch pressed?
The power window except for the one at the driver’s seat cannot be operated
if the window lock switch is pressed. ( P. 187)
●The auto power off function will be operated if the vehicle is left in
ACCESSORY or IGNITION ON mode (the engine is not operating) for a
period of time. ( P. 233)
If you think something is wrong
The engine does not start
The shift lever cannot be shifted from P even if you depress the brake
pedal
The steering wheel cannot be turned after the engine is stopped
The windows do not open or close by operating the power window
switches
The engine switch is turned off automatically