2019 LEXUS UX250H warning light

3416-3. Do-it-yourself maintenance
6
Maintenance and care
■Checking fluid level
The brake fluid level should be
between the “MAX” and “MIN” lines
on the tank.
■Adding fluid
Make sure to check the fluid type and
prepare the necessary item.
 Fluid type
FMVSS No.116 DOT 3 or SAE J1703
brake fluid
FMVSS No.116 DOT 4 or SAE J1704
brake fluid
Items
Clean funnel
■Brake fluid can absorb moisture from
the air
Excess moisture in the brake fluid can cause
a dangerous loss of braking efficiency. Use
only newly opened brake fluid.
If none of the washer do not work or
the “Windshield Washer Fluid Low”
appears on the multi-information dis-
play, the washer tank may be empty.
Add washer fluid.
WARNING
■When the electric cooling fans are
operating
Do not touch the engine compartment.
With the power switch in ON, the elec-
tric cooling fans may automatically start
to run if the air conditioning is on and/or
the coolant temperature is high. Be sure
the power switch is OFF when working
near the electric cooling fans or radiator
grille.
Checking and adding the brake
fluid
WARNING
■When filling the reservoir
Take care as brake fluid can harm your
hands and eyes and damage painted sur-
faces.
If fluid gets on your hands or in your eyes,
flush the affected area with clean water
immediately.
If you still experience discomfort, see a
doctor.
NOTICE
■If the fluid level is low or high
It is normal for the brake fluid level to go
down slightly as the brake pads wear out
or when the fluid leve l in the accumulator
is high.
If the reservoir need s frequent refilling,
there may be a serious problem.
Adding the washer fluid

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

3486-3. Do-it-yourself maintenance
■Run-flat tires
●The run-flat tires are for only this vehicle.
Do not use the tires on other vehicles.
●Do not mix run-flat tires and normal tires.
●If non-genuine Lexus wheels are used, it
may be impossible to sufficiently demon-
strate the performance of run-flat tires.
Your vehicle is equipped with a tire
pressure warning system that uses tire
pressure warning valves and transmit-
ters to detect low tire inflation pressure
before serious problems arise.
If the tire pressure drops below a
predetermined level, the driver is
warned by a screen display and a
warning light. ( P.387, 395)
 The tire pressure detected by the
tire pressure warning system can be
displayed on the multi-information
display. ( P.87)
The illustration used is intended as an
example, and may differ from the image
that is actually displayed on the multi-infor-
mation display.
■Routine tire inflation pressure checks
The tire pressure warning system does not
replace routine tire inflation pressure
checks. Make sure to check tire inflation pressure as part of your routine of daily
vehicle checks.
■Tire inflation pressure
●It may take a few minutes to display the
tire inflation pressu
re after the power
switch is turned to ON. It may also take a
few minutes to display the tire inflation
pressure after inflatio n pressure has been
adjusted.
●Tire inflation pressure changes with tem-
perature. The displaye d values may also
be different from the values measured
using a tire pressure gauge.
■Situations in which the tire pressure
warning system may not operate prop-
erly
●In the following cases, the tire pressure
warning system may not operate prop-
erly.
• If non-genuine Lexus wheels are used.
• A tire has been replaced with a tire that is
not an OE (Original Equipment) tire.
• A tire has been replaced with a tire that is
not of the specified size.
• Tire chains etc. are equipped.
• An auxiliary-supported run-flat tire is equipped.
• If a window tint that affects the radio wave signals is installed.
• If there is a lot of snow or ice on the vehi- cle, particularly around the wheels or
wheel housings.
• If the tire inflation pressure is extremely higher than the specified level.
• If wheels without tire pressure warning
valves and transmitters are used.
• If the ID code on the tire pressure warn- ing valves and transmitters is not regis-
tered in the tire pressure warning
computer.
●Performance may be af fected in the fol-
lowing situations.
• Near a TV tower, electric power plant,
gas station, radio stat ion, large display,
airport or other fac ility that generates
strong radio waves or electrical noise
• When carrying a portable radio, cellular
phone, cordless phone or other wireless
communication device
If tire position information is not correctly
displayed due to the radio wave conditions,
Tire pressure warning system

3506-3. Do-it-yourself maintenance
For vehicles sold in Canada
When replacing tires or wheels, tire
pressure warning valves and transmit-
ters must also be installed.
When new tire pressure warning valves
and transmitters are installed, new ID
codes must be registered in the tire pres-
sure warning computer and the tire pres-
sure warning system mu st be initialized.
(  P.352)
■When replacing the tires and wheels
If the ID code of the tire pressure warning
valve and transmitter is not registered, the
tire pressure warning system will not work
properly. After driving for about 20 min-
utes, the tire pressure warning light blinks
for 1 minute and stays on to indicate a sys-
tem malfunction.
Installing tire pressure warning
valves and transmittersNOTICE
■Repairing or replac ing tires, wheels,
tire pressure warning valves, trans-
mitters and tire valve caps
●When removing or fitting the wheels,
tires or the tire pressure warning
valves and transmitters, contact your
Lexus dealer as the tire pressure warn-
ing valves and transmitters may be
damaged if not handled correctly.
●Make sure to install the tire valve caps.
If the tire valve caps are not installed,
water could enter the tire pressure
warning valves and the tire pressure
warning valves could be bound.
●When replacing tire valve caps, do not
use tire valve caps other than those
specified. The cap may become stuck.

3516-3. Do-it-yourself maintenance
6
Maintenance and care
■The tire pressure warning system
must be initialized in the following
circumstances:
 When rotating the tires.
 When the tire inflation pressure is
changed such as when changing tire
size. (When there are multiple spec-
ified pressures)
 After registering the ID codes.
( P.352)
When the tire pressure warning system
is initialized, the current tire inflation
pressure is set as the benchmark pres-
sure.
■How to initialize the tire pressure
warning system
1
Park the vehicle in a safe place and
stop the hybrid system for 20 min-
utes or more.
Initialization cannot be performed while
the vehicle is moving.
2Adjust the tire inflation pressure to
the specified cold tire inflation pres-
sure level.
Make sure to adjust the tire pressure to the
specified cold tire inflation pressure level.
The tire pressure warning system will oper-
ate based on this pressure level.
3Start the hybrid system ( P.162)
4
Press or of the meter con-
trol switches and select .
5
Press or of the meter con-
trol switches and select “Vehicle
Settings”, then press “OK”.
6
Press or of the meter con-
trol switches and select “TPWS”,
then press “OK”.
7
Press or of the meter con-
trol switches and select “Set Pres-
sure”. Then press and hold “OK”
until the tire pressure warning light
starts blinking.
A message is displayed on the multi-infor-
mation display. Also, “--” is displayed for
inflation pressure of each tire on the multi-
information display while the tire pressure
warning system determines the position.
8Drive at approximately 25 mph
(40 km/h) or more for approxi-
mately 10 to 30 minutes.
When initialization is complete, the infla-
tion pressure of each tire will be displayed
on the multi-information display.
Even if the vehicle is not driven at approxi-
mately 25 mph (40 km/h) or more, initial-
NOTICE
■To avoid damage to the tire pressure
warning valves and transmitters
When a tire is repaired with liquid seal-
ants, the tire pressure warning valve and
transmitter may not operate properly. If a
liquid sealant is used , contact your Lexus
dealer or other qualified service shop as
soon as possible. After use of liquid seal-
ant, make sure to re place the tire pres-
sure warning valve and transmitter when
repairing or replacing the tire.
Initializing the tire pressure
warning system

3526-3. Do-it-yourself maintenance
ization can be completed by driving for a
long time. However, if initialization does not
complete after driving for 1 hour or more,
park the vehicle in a safe place for approxi-
mately 20 minutes and then drive the vehi-
cle again.
■When initializing
●Initialization is performed while driving at
a vehicle speed of approximately 25 mph
(40 km/h) or more.
●Make sure to carry out initialization after
adjusting the tire inflation pressure. Also,
make sure the tires are cold before carry-
ing out initialization or tire inflation pres-
sure adjustment.
●The tire pressure warning system can be
initialized by yourse lf, but depending on
the driving conditions and driving envi-
ronment, initialization may take some
time to complete.
■The initialization operation
●If you have accidenta lly turned the power
switch off during initialization, it is not
necessary to manually restart the initial-
ization again, as initialization will restart
automatically the next time the power
switch is turned to ON.
●If you accidentally perform initialization
when initialization is not necessary, adjust
the tire inflation pres sure to the specified
level when the tires are cold, and conduct
initialization again.
●While the position of each tire is being
determined and the inflation pressures
are not being displayed on the multi-
information display, if the inflation pres-
sure of a tire drops, the tire pressure
warning light will come on.
■If the tire pressure warning system is not
initialized properly
●In the following situations, initialization
may take longer than usual to be com-
pleted or may not be possible. Normally,
initialization completes within approxi-
mately 30 minutes.
• Vehicle is not driven at approximately 25 mph (40 km/h) or more
• Vehicle is driven on unpaved roads
• Vehicle is driven near other vehicles and system cannot recognize tire pressure
warning valve and transmitters of your
vehicle over those of other vehicles
If initialization does no t complete after driv-
ing for 1 hour or more, park the vehicle in a
safe place for approximately 20 minutes
and then drive the vehicle again.
●If the vehicle is reversed during initializa-
tion, the data up to that point is reset, so
perform the initiali zation procedure
again from the beginning.
●In the following situations, initialization
will not be started or was not completed
properly and the system will not operate
properly. Perform the initialization proce-
dure again.
• If, when attempting to start initialization, the tire pressure warning light does not
blink 3 times.
• If, when the vehicle has been driven for about 20 minutes after performing ini-
tialization, the tire pressure warning light
blinks for approximately 1 minute and
then illuminates.
If initialization canno t be completed after
performing the above procedure, contact
your Lexus dealer.
Every tire pressure warning valve and
transmitter has a unique ID code.
When replacing a tire pressure warn-
ing valve and transmitter, it is necessary
to register the ID code.
WARNING
■When initializing the tire pressure
warning system
Do not initialize tire inflation pressure
without first adjusting the tire inflation
pressure to the spec ified level. Other-
wise, the tire pressure warning light may
not come on even if the tire inflation pres-
sure is low, or it may come on when the
tire inflation pressure is actually normal.
Registering ID codes

3536-3. Do-it-yourself maintenance
6
Maintenance and care
When registering the ID codes, per-
form the following procedure.
1Park the vehicle in a safe place, wait
for approximately 20 minutes, and
then start the hybrid system.
( P.162)
2 Press or of the meter con-
trol switches and select .
3 Press or of the meter con-
trol switches and select “Vehicle
Settings”, then press “OK”.
4 Press or of the meter con-
trol switches an d select “TPWS”,
then press “OK”.
5 Press or of the meter con-
trol switches and select “Change
Wheel Set”. Then press and hold
“OK” until the tire pressure warning
light starts slowly blinking 3 times.
Then a message will be displayed on the
multi-information display.
When registration is being performed, the
tire pressure warning light will blink for
approximately 1 minute then illuminate and
“- -” will be displayed for the inflation pres-
sure of each tire on the multi-information
display.
6Drive at 25 mph (40 km/h) or
more for approximately 10 to 30
minutes.
Registration is complete when the tire
pressure warning light turns off and the
inflation pressure of ea ch tire is displayed
on the multi-information display.
Even if the vehicle is not driven at approxi-
mately 25 mph (40 km/h) or more, regis-
tration can be completed by driving for a
long time. However, if registration does not
complete after driving for 1 hour or more,
perform the procedure again from the
beginning.
7 Initialize the tire pressure warning
system. ( P.351)
■When registering ID codes
●ID code registration is performed while
driving at a vehicle speed of approxi-
mately 25 mph (40 km/h) or more.
●Before performing ID code registration,
make sure that no wheels with tire pres-
sure warning valve and transmitters
installed are near the vehicle.
●Make sure to initializ e the tire pressure
warning system after registering the ID
codes. If the system is initialized before
registering the ID codes, the initialized
values will be invalid.
●ID codes can be registered by yourself,
but depending on the driving conditions
and driving environment, registration
may take some time to complete.
■Canceling ID code registration
●To cancel ID code regi stration after it has
been started, turn the power switch off
before driving the vehicle.
If the vehicle is driven after ID code regis-
tration is started, to cancel registration,
perform the ID code registration start
procedure again and turn the power
switch off before driving.
●If ID code registration has been canceled,
the tire pressure warning light will blink
for approximately 1 minute when the
power switch is turned to ON and then
illuminate. The tire pressure warning sys-
tem will be operational when the tire
pressure warning light turns off.
●If the warning light does not turn off even
after several minutes have elapsed, ID

3546-3. Do-it-yourself maintenance
code registration may not have been can-
celed correctly. To cancel registration,
perform the ID code registration start
procedure again and then turn the power
switch off before driving.
■If ID codes are not registered properly
●In the following situations, ID code regis-
tration may take longer than usual to be
completed or may not be possible. Nor-
mally, registration completes within
approximately 30 minutes.
• Vehicle is not parked for approximately
20 minutes or more before driving
• Vehicle is not driven at approximately 25 mph (40 km/h) or more
• Vehicle is driven on unpaved roads
• Vehicle is driven near other vehicles and system cannot recognize tire pressure
warning valves and tr ansmitters of your
vehicle over those of other vehicles
• Wheel with tire pressure warning valve
and transmitter installed is inside or near
the vehicle
If registration does not complete after driv-
ing for 1 hour or more, perform the ID code
registration procedure again from the
beginning.
●If the vehicle is reve rsed during registra-
tion, the data up to that point is reset, so
perform the registrati on procedure again
from the beginning.
●In the following situations, ID code regis-
tration will not be started or was not com-
pleted properly and the system will not
operate properly. Perform the ID code
registration procedure again.
• If, when attempting to start ID code regis- tration, the tire pressure warning light
does not blink slowly 3 times.
• If, when the vehicle has been driven for about 20 minutes after performing ID
code registration, the tire pressure warn-
ing light blinks for approximately 1 minute
and then illuminates.
●If ID code registration cannot be com-
pleted after performing the above proce-
dure, contact your Lexus dealer.