battery LEXUS NX300h 2018 Repair Manual

3336-3. Do-it-yourself maintenance
LEXUS NX300h Owners Manu-
al_USA_OM78212U 6
Maintenance and care The 12-volt battery is located in the left-
hand side of luggage compartment.
■
Before recharging
When recharging, the 12-volt battery pro-
duces hydrogen gas which is flammable
and explosive. Therefore, observe the fol-
lowing precautions before recharging: ●
If recharging with the 12-volt battery
installed on the vehicle, be sure to discon-
nect the ground cable. ●
Make sure the power switch on the char-
ger is off when connecting and discon-
necting the charger cables to the 12-volt
battery. ■
After recharging/reconnecting the 12-
volt battery ●
The hybrid system may not start. Follow
the procedure below to initialize the sys-
tem.
1 Shift the shift lever to P.
2 Open and close any of the doors.
3 Restart the hybrid system.
●
Unlocking the doors using the smart
access system with pu sh-button start may
not be possible immediately after recon-
necting the 12-volt battery. If this hap-
pens, use the wireless remote control or
the mechanical key to lock/unlock the
doors.
●
Start the hybrid system with the power
switch in ACCESSORY mode. The WARNING■
When adding washer fluid
Do not add washer fluid when the hybrid
system is hot or operating as washer fluid
contains alcohol and may catch fire if
spilled on the engine etc.
NOTICE■
Do not use any fluid other than
washer fluid
Do not use soapy water or engine anti-
freeze instead of washer fluid.
Doing so may cause streaking on the
vehicle’s painted surfaces, as well as
damaging the pump leading to problems
of the washer fluid not spraying. ■
Diluting washer fluid
Dilute washer fluid with water as neces-
sary.
Refer to the freezing temperatures listed
on the label of the washer fluid bottle. 12-volt battery
Location

334 6-3. Do-it-yourself maintenance
LEXUS NX300h Owners Manu-
al_USA_OM78212U hybrid system may not start with the
power switch turned off. However, the
hybrid system will operate normally from
the second attempt.●
The power switch mode is recorded by
the vehicle. If the 12-volt battery is recon-
nected, the vehicle will return the power
switch mode to the status it was in before
the 12-volt battery was disconnected.
Make sure to turn off the power before
disconnect the 12- volt battery. Take extra
care when connecting the 12-volt battery
if the power switch mode prior to dis-
charge is unknown.
If the system will not st art even after multiple
attempts at all methods above, contact your
Lexus dealer.
WARNING■
Chemicals in the 12-volt battery
The 12-volt battery contains poisonous
and corrosive sulfuric acid and may pro-
duce hydrogen gas which is flammable
and explosive. To reduce the risk of death
or serious injury, take the following pre-
cautions while working on or near the 12-
volt battery: ●
Do not cause sparks by touching the
12-volt battery terminals with tools.●
Do not smoke or light a match near the
12-volt battery.
●
Avoid contact with eyes, skin and
clothes.
●
Never inhale or swallow electrolyte.
●
Wear protective safety glasses when
working near the 12-volt battery.
●
Keep children away from the 12-volt
battery.
■
Where to safely charge the 12-volt
battery
Always charge the 12-volt battery in an
open area. Do not charge the 12-volt bat-
tery in a garage or closed room where
there is insuffic ient ventilation. ■
Emergency measures regarding
electrolyte ●
If electrolyte gets in your eyes
Flush your eyes with clean water for at
least 15 minutes and get immediate
medical attention. If possible, continue
to apply water with a sponge or cloth
while traveling to the nearest medical
facility. ●
If electrolyte gets on your skin
Wash the affected area thoroughly. If
you feel pain or burning, get medical
attention immediately. ●
If electrolyte gets on your clothes
It can soak through clothing on to your
skin. Immediately take off the clothing
and follow the procedure above if nec-
essary. ●
If you accidentally swallow electrolyte
Drink a large quantity of water or milk.
Get emergency medical attention
immediately. ■
When handling the 12-volt battery
→ P.393 ■
When disconnecting the 12-volt bat-
tery
Do not disconnect the negative (-) termi-
nal on the body side as shown. The dis-
connected negative (-) terminal may
touch the positive (+) terminal, which
may cause a short and result in death or
serious injury.

3356-3. Do-it-yourself maintenance
LEXUS NX300h Owners Manu-
al_USA_OM78212U 6
Maintenance and care 1 Lift the deck board and attach the
hook. ( → P.285)
2 Remove the left side deck board.
3 Remove the cover after removing
the chip.
Press
Pull out
Make sure that the 12-volt battery ter-
minals are not corroded and that there
are no loose connections, cracks, or loose clamps.
Terminals
Hold-down clamp
Insert the left side auxiliary box.
1 Push up center position
2 Insert
3 PressNOTICE■
When recharging the 12-volt battery
Never recharge the 12 -volt battery while
the hybrid system is operating. Also, be
sure all accessories are turned off.
Removing the 12-volt battery
maintenance cover
Exterior A
B Installing the 12-volt battery
maintenance cover A
B

3476-3. Do-it-yourself maintenance
LEXUS NX300h Owners Manu-
al_USA_OM78212U 6
Maintenance and care 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.
1 Take out the mechanical key.
2 Remove the cover. To prevent damage to the key, cover the tip 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
Replacing the battery

348 6-3. Do-it-yourself maintenance
LEXUS NX300h Owners Manu-
al_USA_OM78212U of the flathead screwdriver with a tape.
3 Remove the depleted battery.Insert a new battery with the “+” terminal
facing up.
■
When the card key battery needs to be
replaced (if equipped)
The battery for th e 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 syst em with push-but-
ton start and wireless remote control will
not function properly.
●
The operational rang e will be reduced.
WARNING
■
Removed battery and other parts
These parts are small and if swallowed by
a child, they can cause 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.

357
LEXUS NX300h Owners Manu-
al_USA_OM78212U 7 7
When trouble arises When trouble arises7-1. Essential information
Emergency flashers.................. 358
If your vehicle has to be stopped in
an emergency .......................... 358
7-2. Steps to take in an emergency
If your vehicle needs to be towed
........................................................ 360
If you think something is wrong
........................................................ 363
If a warning light turns on or a
warning buzzer sounds ....... 365
If a warning message is displayed
........................................................ 374
If you have a flat tire.................. 377
If the hybrid system will not start
........................................................ 385
If you lose your keys ................. 386
If the fuel filler door cannot be
opened........................................ 387
If the electronic key does not
operate properly .................... 387
If the 12-volt battery is discharged
........................................................ 390
If your vehicle overheats ........ 394
If the vehicle becomes stuck 397

358 7-1. Essential information
LEXUS NX300h Owners Manu-
al_USA_OM78212U 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.
2 Shift 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

3717-2. Steps to take in an emergency
LEXUS NX300h Owners Manu-
al_USA_OM78212U 7
When trouble arises ■
Brake Override System/Drive-S tart Control warning light *
*
: 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 no t 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 light Details/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.

3757-2. Steps to take in an emergency
LEXUS NX300h Owners Manu-
al_USA_OM78212U 7
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.367)
●
Malfunction of the charging system
The charging system warning light comes
on. ( → P.365)
■
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.394■
If “Maintenance required for Traction
battery cooling parts at your dealer” is
shown
The filter may be clogge d, or the air intake
vents or ducts may be blocked. Have the
vehicle inspected by your Lexus dealer.
■
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-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 ⎯ Sounds Indicates 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

376 7-2. Steps to take in an emergency
LEXUS NX300h Owners Manu-
al_USA_OM78212U charged” ( → P.390).*
: Displays for about 6 seconds ■
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. Releas e 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.209, 367)●
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 oi l 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.329)■
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.329)■
If “See Owner’s Manual” is shown ●
If the following messages are shown, fol-
lowing the instruct ions, accordingly.
• “Engine Coolant Temp High” ( → P.394)
• “Aux Battery Low” ( → P.375)●
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 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”