2019 LEXUS NX300H battery

3496-3. Do-it-yourself maintenance
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Maintenance and care
■When the card key battery needs to be
replaced (if equipped)
The battery for the card key is available only
at Lexus dealers. Your Lexus dealer can
replace the battery for you.
■If the electronic key battery is depleted
The following symptoms may occur:
●The smart access system with push-but-
ton start and wireless remote control will
not function properly.
●The operationa l range will be reduced.
Prepare the following before replacing
the battery:
Flathead screwdriver
 Lithium battery CR2032
■Use a CR2032 lithium battery
●Batteries can be purchased at your Lexus
dealer, local electrical appliance shops or
camera stores.
●Replace only with the same or equivalent
type recommended by the manufacturer.
●Dispose of used batteries according to
the local laws.
NOTICE
■When using the air conditioning sys-
tem
Make sure that a filter is always installed.
Using the air conditioning system without
a filter may cause damage to the system.
Electronic key battery
Replace the battery with a new one
if it is depleted.
Items to prepare

3506-3. Do-it-yourself maintenance
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1Take out the mechanical key.
2 Remove the cover.
To prevent damage to the key, cover the tip
of the flathead screwdriver with a tape.
3Remove the depleted battery.
Insert a new battery with the “+” terminal
facing up.
Replacing the batteryWARNING
■Removed battery and other parts
These parts are small and if swallowed by
a child, they can cau se choking. Keep
away from children. Failure to do so
could result in death or serious injury.
NOTICE
■For normal operation after replacing
the battery
Observe the following precautions to
prevent accidents:
●Always work with dry hands.
Moisture may cause the battery to
rust.
●Do not touch or move any other com-
ponent inside the remote control.
●Do not bend either of the battery ter-
minals.

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When trouble arises
When trouble arises
7-1. Essential informationEmergency flashers.................. 360
If your vehicle has to be stopped in an emergency .......................... 360
7-2. Steps to take in an emergency If your vehicle needs to be towed........................................................ 362
If you think something is wrong ........................................................ 365
If a warning light turns on or a warning buzzer sounds ....... 367
If a warning message is displayed ........................................................ 376
If you have a flat tire.................. 379
If the hybrid system will not start ........................................................ 387
If you lose your keys ................. 388
If the fuel filler door cannot be opened........................................ 389
If the electronic key does not operate properly .................... 389
If the 12-volt battery is discharged ........................................................ 392
If your vehicle overheats ........ 396
If the vehicle becomes stuck 399

3607-1. Essential information
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7-1.Essential information
Press the switch.
All the turn signal lights will flash. To turn
them off, press the switch once again.
■Emergency flashers
If the emergency flashers are used for a
long time while the hybrid system is not
operating (while the “READY” indicator is
not illuminated), the 12-volt battery may dis-
charge.
1 Steadily step on the brake pedal
with both feet and firmly depress it.
Do not pump the brake pedal repeatedly
as this will increase the effort required to
slow the vehicle.
2Shift the shift lever to N.
If the shift lever is shifted to N
3 After slowing down, stop the vehi-
cle in a safe place by the road.
4 Stop the hybrid system.
If the shift lever cannot be shifted to
N
3 Keep depressing the brake pedal
with both feet to reduce vehicle
speed as much as possible.
4 To stop the hybrid system, press
and hold the power switch for 2
consecutive seconds or more, or
Emergency flashers
The emergency flashers are used to
warn other drivers when the vehicle
has to be stopped in the road due to
a breakdown, etc.
Operating instructions
If your vehicle has to be
stopped in an emergency
Only in an emergency, such as if it
becomes impossible to stop the
vehicle in the normal way, stop the
vehicle using the following proce-
dure:
Stopping the vehicle

3737-2. Steps to take in an emergency
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When trouble arises
■Brake Override System/Drive-S tart Control warning light* (warning buzzer)
*: This light illuminates on the multi-information display.
■SRS warning light
This warning light system monitors the air-
bag sensor assembly, fr ont impact sensors,
side impact sensors (front door), side
impact sensors (rear), driver’s seat position
sensor, driver’s seat be lt buckle switch, front
passenger occupant cl assification system
(ECU and sensors), “AIR BAG ON” indi-
cator light, “AIR BAG OFF” indicator light,
front passenger’s seat belt buckle switch,
driver’s seat belt pretensioner, front passen-
ger’s seat belt pretensioner and force lim-
iter, airbags, interconnecting wiring and
power sources. ( P.32)
■Front passenger detection sensor, seat
belt reminder and warning buzzer
●If luggage is placed on the front passen-
ger seat, the front passenger detection
sensor may cause th e warning light to
flash and the warning buzzer to sound even if a passenger is not sitting in the
seat.
●If a cushion is placed on the seat, the sen-
sor may not detect a passenger, and the
warning light may not operate properly.
■Electric power steering system warning
light (warning buzzer)
When the 12-volt battery charge becomes
insufficient of the voltage temporarily drops,
the electric power steering system warning
light may come on and the warning buzzer
may sound.
■If the malfunction indicator lamp comes
on while driving
First check the following:
●Is the fuel tank empty?
If it is, fill the fuel tank immediately.
●Is the fuel tank cap loose?
If it is, tighten it securely.
Warning lightDetails/Actions
Brake Override System
Indicates that the accelerato r and brake pedals are being
depressed simultaneously, and the Brake Override System
is operating.
 Release the accelerator pedal and depress the brake
pedal.
Indicates a malfunction in the Brake Override System (with
warning buzzer)
 Have the vehicle inspected by your Lexus dealer
immediately.
Drive-Start Control
Indicates that the shift position was changed and Drive-
Start Control was operated wh ile depressing the accelera-
tor pedal. (with warning buzzer)
 Momentarily release th e accelerator pedal.
Indicates a malfunction in th e Drive-Start Control system
(with warning buzzer)
 Have the vehicle inspected by your Lexus dealer
immediately.

3777-2. Steps to take in an emergency
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When trouble arises
The warning lights and warning buzzers op erate as follows depending on the con-
tent of the message. If a message indicates the need for inspection by a dealer, have
the vehicle inspected by your Lexus dealer immediately.
*: A buzzer sounds the first time a message is shown on the multi-information display.
■System warning lights
The master warning light does not come on
or flash in the following cases. Instead, a
separate system warning light will come on
along with a message shown on the multi-
information display.
●Malfunction of the ABS
The ABS warning light comes on.
(  P.369)
●Malfunction of the charging system
The charging system warning light comes
on. ( P.367)
■If “Hybrid System Overheated Reduced
Output Power” is shown
This message may be displayed when driv-
ing under severe operating conditions. (For example, when driving up a long steep hill.)
Handling method:
P.396
■If “Aux Battery Low” is shown
●When the display goes off after several
seconds*
Maintain the hybrid system operation for
more than 15 minutes and charge the 12-
volt battery.
●When the display does not go off
Start up the hybrid system using the pro-
cedures for “If the 12-volt battery is dis-
charged” ( P.392).
*: Displays for about 6 seconds
Messages and warnings
System
warning light
Warning buzzer*Warning
Comes onSounds
Indicates an important situation, such as
when a system related to driving is malfunc-
tioning or that danger may result if the cor-
rection procedure is not performed

Comes on or
flashes
Sounds
Indicates an important situation, such as
when the systems shown on the multi-infor-
mation display may be malfunctioning
FlashesSoundsIndicates a situation, such as when damage
to the vehicle or danger may result
Comes onDoes not sound
Indicates a condition, such as malfunction of
electrical components, their condition, or
indicates the need for maintenance
FlashesDoes not sound
Indicates a situation, such as when an opera-
tion has been performed incorrectly, or indi-
cates how to perform an operation correctly

3787-2. Steps to take in an emergency
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■If “Traction Battery Needs to be Pro-
tected Refrain From the Use of N Posi-
tion” is shown
This message may be displayed when the
shift lever is in N.
As the hybrid battery (traction battery) can-
not be charged when the shift lever is in N,
when the vehicle is to be stopped for a long
period of time, shift the shift lever to P.
■If “Traction battery needs to be pro-
tected. Shift into P to restart.” is shown
Message is displayed when the remaining
charge for the hybrid battery (traction bat-
tery) is low, because vehicle has been
shifted N for a long period of time.
When operating the vehicle, restart the
hybrid system.
■If “Shift to P Before Exiting Vehicle” is
shown
Message is displayed when the driver’s
door is opened with out turning the power
switch to OFF with the shift lever in any
position other than P.
Shift the shift lever to P.
■If “Shift Is in N Release Accelerator
Before Shifting” is shown
Message is displayed when the accelerator
pedal has been depressed and the shift
lever is in N. Release the accelerator pedal
and shift the shift lever to D, S or R.
■If “Depress Brake When Vehicle Is
Stopped Hybrid Syst em May Overheat”
is shown
Message is displayed when the accelerator
pedal is depressed to maintain the vehicle
position when stopped on a upward slope,
etc.
If this continues, th e hybrid system may
overheat.
Release the accelerator pedal and depress
the brake pedal.
■If “Front Camera Unavailable” or “Front
Camera Unavailable Remove Debris
On Windshield” is shown
The following systems may be suspended
until the problem shown in the message is
resolved. ( P.208, 369)
●PCS (Pre-Collision System)
●LDA (Lane Departure Alert with steering
control)
●Dynamic radar cruise control with full-
speed range
●Adaptive High-beam System
●Automatic High Beam
■If “Oil Maintenance Required Soon” is
shown
Indicates that the engine oil is scheduled to
be changed. (The indicator will not work
properly unless the oil maintenance data
has been reset.)
Check the engine oil, and change if neces-
sary. After changing th e engine oil, the oil
change system should be reset. ( P.330)
■If “Oil Maintenance Required” is shown
Indicates that the engine oil should be
changed. (After the engine oil is changed
and the oil maintenance data has been
reset.)
Check and change the en gine oil, and oil fil-
ter by your Lexus dealer. After changing the
engine oil, the oil change system should be
reset. ( P.330)
■If “See Owner’s Manual” is shown
●If the following messages are shown, fol-
lowing the instruct ions, accordingly.
• “Engine Coolant Temp High” ( P.396)
• “Aux Battery Low” ( P.377)
●If the following messages are shown,
there may be a malfunction.
Immediately have the vehicle inspected
by your Lexus dealer.
• “Hybrid System Malfunction”
•“Check Engine”
• “Hybrid Battery System Malfunction”
• “Accelerator System Malfunction”
• “Braking Power Low”
• “Smart Access System Malfunction”
●If “Maintenance required for Traction bat-
tery cooling parts” is shown, the filters
may be clogged, the air intake vents may
be blocked, or there may be a gap in the
duct. Therefore, perform the following
correction procedure.
• If the air intake vents of the hybrid battery (traction battery) are dirty, perform the
procedure on P. 316 to clean them.
• If the warning message is shown when

3797-2. Steps to take in an emergency
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When trouble arises
the air intake vents of the hybrid battery
(traction battery) are not dirty, have the
vehicle inspected by your Lexus dealer.
●If the following messages are shown,
there may be a malfunction.
Immediately stop the vehicle in a safe
place and contact your Lexus dealer.
Continuing to drive the vehicle may be
dangerous.
• “Oil Pressure Low”
• “Charging System Malfunction”
■Warning buzzer
 P.374
 Stop the vehicle in a safe place on a
hard, flat surface.
 Set the parking brake.
 Shift the shift lever to P.
 Stop the hybrid system.
 Turn on the emergency flashers.
( P.360)
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 12-volt bat-
tery may be deteriorating. Have the vehi-
cle inspected by your Lexus dealer.
■“Aux Battery Low” is frequently
shown
The 12-volt battery may have deterio-
rated. As the battery may discharge in
this state when left unattended, have the
battery inspected by your Lexus dealer.
If you have a flat tire
Your vehicle is equipped with a
spare tire. The flat tire can be
replaced with the spare tire.
For details about tires: P.337
WARNING
■If you have a flat tire
Do not continue driving with a flat tire.
Driving even a short distance with a flat
tire can damage the tire and the wheel
beyond repair, which could result in an
accident.
Before jacking up the vehicle