2020 LEXUS RX450H battery

6578-2. Steps to take in an emergency
8
When trouble arises
RX350/RX350L_U
*1: Driver's and front passenger's seat belt warning buzzer:
The driver’s seat belt warning buzzer sounds to alert the driver that his or her seat belt
is not fastened. Once the engine switch is turned to IGNITION ON mode, the
buzzer sounds for 6 seconds. If the vehicl e reaches a speed of 12 mph (20 km/h), the
buzzer sounds once. If the seat belt is still unfastened after 24 seconds, the buzzer will
sound intermittently for 10 se conds. Then, if the seat belt is still unfastened, the buzzer
will sound in a different to ne for 20 more seconds.
The front passenger’s seat belt warning buzzer sounds to alert the front passenger
that his or her seat belt is not fastened. Th e buzzer sounds once if the vehicle reaches
a speed of 12 mph (20 km/h). If the seat belt is still unfastened after 24 seconds, the
buzzer will sound intermittently for 10 seconds. Then, if the seat belt is still unfastened,
the buzzer will sound in a different tone for 20 more seconds.
*2: Rear passengers’ seat belt warning buzzer:
The rear passengers’ seat belt warning bu zzer sounds to alert the rear passengers
that his or her seat belt is not fastened. The buzzer so unds for 6 seconds after the
vehicle reaches a speed of 20 km/h (12 mph). Then, if the seat belt is still unfastened,
the buzzer will sound in a different tone for 24 more seconds.
■SRS warning light
This warning light system monitors the airbag sensor assembly, front impact sensors, side
impact sensors (front door), side impact se nsors (rear), driver’s seat position sensor,
driver’s seat belt buckle sw itch, front passenger occupant classification system (ECU and
sensors), “AIR BAG ON” indicator light, “A IR BAG OFF” indicator light, front passen-
ger’s seat belt buckle switch, driver’s seat belt pretension er, front passenger’s seat belt
pretensioner and force limiter, airbags, in terconnecting wiring and power sources.
(  P. 36)
■Front passenger detection sensor, seat belt reminder and warning buzzer
●If luggage is placed on the front passenger seat, the front passenger detection sensor
may cause the warning light to flash and the warning buzzer to sound even if a passen-
ger is not sittin g in the seat.
●If a cushion is placed on the seat, the sens or may not detect a passenger, and the warn-
ing light may not operate properly.
■Electric power steering system warning light (warning buzzer)
When the battery charge becomes insufficien t or the voltage temporarily drops, the
electric power steering system warning li ght may come on and the warning buzzer may
sound.
Master warning light A buzzer sounds and the warning light comes on and flashes to
indicate that the master warnin g system has detected a malfunc-
tion.
 P. 661
Warning lightWarning light/Details/Actions

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

6658-2. Steps to take in an emergency
8
When trouble arises
RX350/RX350L_U
■If “Maintenance Required Visit Your Dealer” is displayed (U.S.A. only)
Indicates that all maintenance is requir ed to correspond to the driven distance
on the maintenance schedule
*.
Comes on approximately 5000 miles (8000 km) after the message has
been reset.
(The indicator will not work properly unless the message has been reset.)
Perform the necessary maintenance. Please reset the message after the main-
tenance is performed. ( P. 585)
*: Refer to the separate “Scheduled Mainte nance” or “Owner’s Manual Supplement”
for the maintenance interval applicable to your vehicle.
■System warning lights
The master warning light does not come on or flash in the following cases. Instead, a sep-
arate system warning light will come on along with a message shown on the multi-infor-
mation display.
●“Antilock Brake System Malfunction Visit Your Dealer”:
The ABS warning light comes on. ( P. 654)
●“Charging System Malfunction See Ow ner’s Manual” (F SPORT models):
The charging system wa rning light comes on. (P. 654)
■Warning buzzer
 P. 658
NOTICE
■“High Power Consumption Partial Limit On AC/Heater Operation” is frequently
shown
There is a possible malfunction relating to the charging system or the battery may be
deteriorating. Have the vehicle inspected by your Lexus dealer.

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

6838-2. Steps to take in an emergency
8
When trouble arises
RX350/RX350L_U
One of the following may be the cause of the problem:
●One or both of the battery terminals may be disconnected.
●The battery may be discharged. (P. 687)
●There may be a malfunction in the steering lock system.
Contact your Lexus dealer if the problem cannot be repaired, or if repair procedures
are unknown.
When the engine does not start, the follo wing steps can be used as an interim
measure to start the engine if the engine switch is functioning normally.
Turn the engine switch to IGNITION ON mode and check that the parking
brake is set. ( P. 232, 247)
Shift the shift lever to P.
Turn the engine switch to ACCESSORY mode.
Press and hold the engine switch for about 15 seconds while depressing the
brake pedal firmly.
Even if the engine can be started using the above steps, the system may be mal-
functioning. Have the vehicle in spected by your Lexus dealer.
The starter motor does not turn over, the interior lights and headlights
do not turn on, or the horn does not sound.
Emergency start function
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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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