battery LEXUS UX250H 2019 Repair Manual

3376-3. Do-it-yourself maintenance
6
Maintenance and care
Fuse boxes (P.370)
Engine coolant reservoir ( P.339)
Engine oil filler cap ( P.338)
Power control unit coolant reservoir ( P.340)
Brake fluid reservoir ( P.341)
Radiator ( P.340)
Condenser ( P.340)
Electric cooling fans
Engine oil level dipstick ( P.337)
Washer fluid tank ( P.341)
■12-volt battery
 P.342
With the engine at operating tempera-
ture and turned off, check the oil level
Engine compartment
Components
A
B
C
D
E
F
G
H
I
J
Checking and adding the engine
oil

3426-3. Do-it-yourself maintenance
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 ACC. The hybrid system may
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

3436-3. Do-it-yourself maintenance
6
Maintenance and care
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.
1Open the right side deck board.
( P.297)
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 insufficient 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.409
NOTICE
■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
cover

3446-3. Do-it-yourself maintenance
2Remove the right side deck board.
3 Remove the 12-volt battery cover.
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 Check the 12-volt battery condition by
indicator color.
Blue: Good condition
Red: Charging is necessary.
Have the vehicle inspected by your Lexus
dealer.
Clear: Replacement is necessary.
Have the 12-volt battery checked by your
Lexus dealer.
1Install the 12-volt battery cover.
Exterior
A
B
Checking 12-volt battery condi-
tion
Installing the 12-volt battery
cover
A
B
C

3656-3. Do-it-yourself maintenance
6
Maintenance and care
filter.
Remove the dust from the air intake
vent with a vacuum cleaner etc.
Make sure to only use a vacuum to suck
out dust and clogs. Attempting to blow out
dust and clogs using an airgun etc. may
push it into the air intake vent.
If dust and clogs cannot be completely
removed with the air intake vent cover
installed, remove the cover and clean
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.
■To prevent damage to the filter cover
When moving the filter cover in the
direction of arrow to release the fitting,
pay attention not to apply excessive force
to the claws. Otherwise, the claws may
be damaged.
Cleaning the hybrid battery
(
traction battery) air intake
v
ent and filter
To prevent the fuel economy from
being affected, visually inspect the
hybrid battery (traction battery) air
intake vent periodically for dust and
clogs. If it is dusty or clogged or if
“Maintenance required for Traction
battery cooling parts See owner’s
manual” is shown on the multi-infor-
mation display, clean the air intake
vent using the following proce-
dures:
Cleaning the air intake vent
If dust and clogs cannot be com-
pletely removed

3676-3. Do-it-yourself maintenance
6
Maintenance and care
7Install the air intake vent cover.
1
Insert the tab of the cover as shown
in the illustration.
2
Push the cover to engage the 5
claws.
8
Using a Phillips screwdriver, install
the clip.
■Scheduled maintenance of the air
intake vent is necessary when
In some situations such as when the vehicle
is used frequently or in heavy traffic or dusty
areas, the air intake vent may need to be
cleaned more regularly. For details, refer to
the “Warranty and Service Guide”,
“Owner’s Manual Supplement” or “Sched-
uled Maintenance”.
■Cleaning the air intake vent
●Dust in the air intake vent may interfere
with the cooling of the hybrid battery
(traction battery). If charging/discharging
of the hybrid battery (traction battery)
becomes limited, the distance that the
vehicle can be driven using the electric
motor (traction motor) may be reduced
and the fuel economy may be reduced. Inspect and clean the air intake vent peri-
odically.
●Improper handling of the air intake vent
cover and filter may result in damage to
them. If you have any concerns about
cleaning the filter, contact your Lexus
dealer.
■If “Maintenance required for Traction
battery cooling parts See owner’s man-
ual” is shown on the multi-information
display
●If this warning message is shown on the
multi-information display, remove the air
intake vent cover and clean the filter.
(
 P.365)
●After cleaning the air intake vent, start
the hybrid system and check that the
warning message is no longer shown. It
may take approximately 20 minutes after
the hybrid system is started until the
warning message disappears. If the warn-
ing message does not disappear, have the
vehicle inspected by your Lexus dealer.
WARNING
■When cleaning the air intake vent
●Do not use water or other liquids to
clean the air intake vent. If water is
applied to the hybrid battery (traction
battery) or other components, a mal-
function or fire may occur.
●Before cleaning the air intake vent,
make sure to turn the power switch off
to stop the hybrid system.
■When removing the air intake vent
cover
Do not touch the service plug located
near the air intake vent. ( P.66)

3686-3. Do-it-yourself maintenance
■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 operational range will be reduced.
■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.
Prepare the following before replacing
the battery:
 Flathead screwdriver
 Small 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 cleaning the air intake vent
When cleaning the air intake vent, make
sure to only use a vacuum to suck out
dust and clogs. If a compressed air blow
gun, etc. is used to blow out dust and
clogs, the dust or clogs may be pushed
into the air intake ve nt, which may affect
the performance of the hybrid battery
(traction battery) and cause a malfunc-
tion.
■To prevent damage to the vehicle
●Do not allow water or foreign matter to
enter the air intake vent when the
cover is removed.
●Carefully handle the removed filter so
that it will not be damaged. If the filter
is damaged, have it replaced with a
new filter by your Lexus dealer.
●Make sure to reinstall the filter and
cover to their original positions after
cleaning.
●Do not install anything to the air intake
vent other than the exclusive filter for
this vehicle or use the vehicle without
the filter installed.
■If “Maintenance required for Traction
battery cooling parts See owner’s
manual” is shown on the multi-infor-
mation display
If the vehicle is continuously driven with
the warning message (indicating that
charging/discharging of the hybrid bat-
tery [traction battery] may become lim-
ited) displayed, the hybrid battery
(traction battery) may malfunction. If the
warning message is shown, clean the air
intake vent immediately.
Electronic key battery
Replace the battery with a new one
if it is depleted.
Items to prepare

3696-3. Do-it-yourself maintenance
6
Maintenance and care
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 using
the small flathead screwdriver.
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 cause choking. Keep
away from children. Failure to do so
could result in death or serious injury.
NOTICE
■When replacing the battery
Use a screwdriver of appropriate size.
Applying excessive force may deform or
damage the cover.
■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.

3706-3. Do-it-yourself maintenance
1Turn the power switch off.
2 Open the fuse box cover.
Engine compartment: type A fuse
box
Push the tab in and lift the lid off.
Engine compartment: type B fuse
box
Push the tab in and lift the lid off.
Left side instrument panel
Remove the lid.
Luggage compartment
Remove the 12-volt battery cover
( P.343) and push the tab in and lift the
lid off.
3 Remove the fuse.
Only type A fuse can be removed using the
pullout tool.
4Check if the fuse is blown.
Replace the blown fuse with a new fuse of
an appropriate amperage rating. The
amperage rating can be found on the fuse
box lid.
Checking and replacing
fuses
If any of the electrical components
do not operate, a fuse may have
blown. If this happens, check and
replace the fuses as necessary.
Checking and replacing fuses

377
7
7
When trouble arises
When trouble arises
7-1. Essential informationEmergency flashers.................. 378
If your vehicle has to be stopped in an emergency .......................... 378
If the vehicle is trapped in rising water............................................ 379
7-2. Steps to take in an emergency If your vehicle needs to be towed......................................................... 381
If you think something is wrong ........................................................ 385
If a warning light turns on or a warning buzzer sounds ....... 386
If a warning message is displayed ........................................................ 395
If you have a flat tire.................. 399
If the hybrid system will not start ........................................................ 400
If you lose your keys ................. 402
If the fuel filler door cannot be opened........................................ 402
If the electronic key does not operate properly .................... 403
If the 12-volt battery is discharged ........................................................ 405
If your vehicle overheats ......... 410
If the vehicle becomes stuck . 413