key battery LEXUS RX450H 2020 Owner's Manual

6638-2. Steps to take in an emergency
8
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

6828-2. Steps to take in an emergency
RX350/RX350L_U
One of the following may be the cause of the problem:
●There may not be sufficient fuel in the vehicle’s tank.
Refuel the vehicle.
●The engine may be flooded.
Try to restart the engine again following correct starting procedures.
( P. 231)
●There may be a malfunction in th e engine immobilizer system. (P. 74)
One of the following may be the cause of the problem:
●The battery terminal connections may be loose or corroded.
●The battery may be discharged. ( P. 687)
The engine starting system may be malfun ctioning due to an electrical problem
such as electronic key battery depletio n or a blown fuse. However, an interim
measure is available to start the engine. ( P. 683)
If the engine will not start
If the engine will not start even though correct starting procedures are being
followed ( P. 231), consider each of the following points:
The engine will not start even thoug h the starter motor operates nor-
mally.
The starter motor turns over slowly , the interior lights and headlights
are dim, or the horn does not sound or sounds at a low volume.
The starter motor does not turn over

6848-2. Steps to take in an emergency
RX350/RX350L_U
■Unlocking the door
Use the mechanical key (P. 121) in order to pe rform the following opera-
tions:
Insert the mechanical key while
pulling on the driver’s door han-
dle.
Unlocking the door.
Turning the key rearward unlocks the
driver’s door. Turning the key again
unlocks the other doors.
Remove the key, return the handle, and then pull the handle again.
If the electronic key does not operate properly
If communication between the electronic key and vehicle is interrupted
( P. 148) or the electronic key ca nnot be used because the battery is
depleted, the smart access system wi th push-button start and wireless
remote control cannot be used. In such cases, the doors can be opened and
the engine can be started by following the procedure below.
Locking and unlocking the doors
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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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6878-2. Steps to take in an emergency
8
When trouble arises
RX350/RX350L_U
If you have a set of jumper (or booster) cables and a second vehicle with a bat-
tery, you can jump start your vehicle by following the steps below.Confirm that the electronic key is
being carried.
When connecting the jumper (or
booster) cables, depe nding on the situa-
tion, the alarm may activate and doors
locked. (
P. 78)
Open the hood ( P. 592)
If the vehicle battery is discharged
The following procedures may be used to start the engine if the vehicle’s bat-
tery is discharged.
You can also call your Lexus deal er or a qualified repair shop.
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6898-2. Steps to take in an emergency
8
When trouble arises
RX350/RX350L_U
■Starting the engine when the battery is discharged
The engine cannot be started by push-starting.
■To prevent battery discharge
●Turn off the headlights and the audio system while the engine is off.
●Turn off any unnecessary electrical components when the vehicle is running at a low
speed for an extended period, such as in heavy traffic.
■When removing the battery terminals
When the battery terminals are removed, the information stored in the ECU is cleared.
Before removing the battery termin als, contact your Lexus dealer.
■Charging the battery
The electricity stored in the battery will disc harge gradually even when the vehicle is not
in use, due to natural discharge and the draini ng effects of certain electrical appliances. If
the vehicle is left for a long time, the battery may discharge, and the engine may be
unable to start. (The battery recharges automatically during driving.)
■When the battery is removed or discharged
●In some cases, it may not be possible to un lock the doors using the smart access system
with push-button start when the battery is discharged. Use the wireless remote control
or the mechanical key to lock or unlock the doors.
●The engine may not start on the first attempt after the battery has recharged but will
start normally after the second attempt. This is not a malfunction.
●The engine switch mode is memorized by the vehicle. When the battery is recon-
nected, the system will return to the mode it was in before the battery was discharged.
Before disconnecting the battery, turn the engine switch off.
If you are unsure what mode the engine switch was in before the battery discharged, be
especially careful when reconnecting the battery.
●The power back door must be initialized. ( P. 138)
■When replacing the battery
●Use a battery with the same case size as the previous battery and an equivalent 20
hour rate capacity (20HR) or greater.
• If the sizes differ, the battery cannot be properly secured.
• If the 20 hour rate capacity is low, even if the time period where the vehicle is not used is a short time, the battery may discharge and the engine may not be able to
start.
●For details, consult your Lexus dealer.

752
RX350/RX350L_UWhat to do if... (Troubleshooting)
What to do if... (Troubleshooting)
●If you lose your mechanical keys, ne
w genuine mechanical keys can be made
by your Lexus dealer. ( P. 121)
●If you lose your electronic keys, the risk of vehicle theft increases significantly.
Contact your Lexus dealer immediately. ( P. 123)
●Is the electronic key battery weak or depleted? ( P. 623)
●Is the engine switch in IGNITION ON mode?
When locking the doors, turn the engine switch off. (P. 232)
●Is the electronic key left inside the vehicle?
When locking the doors, make sure that you have the electronic key on your
person.
●The function may not operate properly du e to the condition of the radio wave.
( P. 148)
●Is the child-protector lock set?
The rear door cannot be opened from in side the vehicle when the lock is set.
Open the rear door from outside and then unlock the child-protector lock.
( P. 127)
If you have a problem, check the foll owing before contacting your Lexus
dealer.
The doors cannot be locked, unlocked, opened or closed
You lose your keys
The doors cannot be locked or unlocked
The rear door cannot be opened

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

759Alphabetical index
RX350/RX350L_U
CareAluminum wheels .............................. 577
Exterior....................................................576
Interior ...................................................... 581
Seat belts ............................................... 582
Self-restoring coat .............................576
Cargo capacity............................210, 698
Cargo hooks .......................................... 536
Cargo net hooks ................................... 536
CD player .................................................427
Chains .......................................................385
Child restraint system............................ 55 Booster seats installation................... 64
Convertible seats installation .......... 62
Front passenger occupant classification system ......................... 47
Infant seats definition .............................61
Infant seats installation ........................ 57
Installing CRS with LATCH anchors ................................................... 67
Installing CRS with seat belts ............61
Installing CRS with top tether strap.......................................................... 70
LATCH anchors ................................... 67 Child safety .................................................54
Airbag precautions.............................. 39
Battery precautions ............. 602, 690
Child restraint system......................... 55
How your child should wear the seat belt .............................. 33
Installing child restraints .................... 55
Moon roof precautions ....................194
Panoramic moon roof precautions ........................................ 198
Power back door precautions......140
Power window lock switch.............187
Power window precautions .......... 190
Rear door child-p rotectors ............ 127
Removed key battery precautions ....................................... 624
Seat belt extender precautions .......................................... 35
Seat belt precautions .......................... 35
Seat heater precautions ................... 521
C

762Alphabetical index
RX350/RX350L_U
Eco drive mode ..................................... 373
Eco Driving Indicator........................... 105
EDR (Event data recorder) ...................10
Electric Power Steering (EPS) ....... 378Warning light ...................................... 655
Electronic key ......................................... 120 Battery-saving function .....................147
If the electronic key does not operate properly............................ 684
Replacing the battery .......................623
Emergency flashers ............................. 644
Emergency, in case of If a warning buzzer sounds.......... 654
If a warning light turns on.............. 654
If a warning message is displayed.............................................. 661
If the battery is discharged ........... 687
If the electronic key does not operate properly............................ 684
If the engine will not start............... 682
If you have a flat tire ......................... 666
If you lose your keys .................. 121, 123
If you think something is wrong ...................................................652
If your vehicle becomes stuck .... 695
If your vehicle has to be stopped in an emergency .. 645
If your vehicle needs to be towed................................................... 646
If your vehicle overheats ................692 Engine
ACCESSORY mode ..................... 232
Compartment ..................................... 594
Engine switch ........................................ 231
Hood........................................................ 592
How to start the engine.................... 231
Identification number.......................700
If your vehicle has to be stopped in an emergency.......... 645
Ignition switch (engine switch) ..... 231
Overheating......................................... 692
Engine coolant Capacity................................................. 702
Checking .............................................. 598
Preparing and checking before winter ....................................384
Engine coolant temperature gauge ........................................................ 86
Engine immobilizer system .................. 74
Engine oil Capacity.................................................700
Checking ...............................................595
Preparing and checking before winter ....................................384
Engine oil maintenance data ............597
Engine switch ........................................... 231
Enhanced VSC ..................................... 378
EPS (Electronic Power Steering) ........ 378 Warning light .......................................655
Event data recorder (EDR)................... 10
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