air conditioning LEXUS UX250H 2019 Owner's Guide

3346-3. Do-it-yourself maintenance
Tire inflation
pressure
( P.361)• Tire pressure gauge
• Compressed air source
Washer fluid
( P.341)
• Water or washer fluid
containing antifreeze
(for winter use)
• Funnel (used only for adding water or washer
fluid)
WARNING
The engine compartment contains many
mechanisms and fluids that may move
suddenly, become hot, or become elec-
trically energized. To avoid death or seri-
ous injury, observe the following
precautions.
■When working on the engine com-
partment
●Make sure that “IGNITION ON” on
the multi-information display and the
“READY” indicator are both off.
●Keep hands, clothi ng and tools away
from the moving fan and engine drive
belt.
●Be careful not to touch the engine,
power control unit, radiator, exhaust
manifold, etc. right after driving as they
may be hot. Oil and other fluids may
also be hot.
●Do not leave anything that may burn
easily, such as paper and rags, in the
engine compartment.
●Do not smoke, cause sparks or expose
an open flame to fuel. Fuel fumes are
flammable.
■When working near the electric cool-
ing fans or radiator grille
Be sure the power switch is OFF.
With power switch in ON, the electric
cooling fans may automatically start to
run if the air conditioning is on and/or the
coolant temperature is high. ( P.340)
ItemsParts and tools■Safety glasses
Wear safety glasses to prevent flying or
falling material, fluid spray, etc. from get-
ting in your eyes.
NOTICE
■If you remove the air cleaner filter
Driving with the air cleaner filter
removed may cause excessive engine
wear due to dirt in the air.

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

3646-3. Do-it-yourself maintenance
1Turn the power switch off.
2 Open the glove box. Remove the
partition. ( P.294)
3 Remove the panel.
4 Unlock the filter cover ( ), pull
the filter cover out of the claws
( ), and remove the filter cover. 5
Remove the filter case.
6 Remove the air conditioning filter
from the filter case and replace it
with a new one.
The “ UP” marks shown on the filter and
the filter case should be pointing up.
■Checking interval
Inspect and replace the air conditioning fil-
ter according to the maintenance schedule.
In dusty areas or areas with heavy traffic
flow, early replacement may be required.
(For scheduled maintenance information,
please refer to the “Owner’s Manual Sup-
plement” or “Scheduled Maintenance”.)
■If air flow from the vents decreases dra-
matically
The filter may be clogged. Check the filter
and replace if necessary.
■Air conditioning filt er with deodorizing
function
When fragrances are placed in your vehi-
cle, the deodorizing effect may become
significantly weakened in a short period.
When an air conditioning odor comes out
continuously, replace the air conditioning
Air conditioning filter
The air conditioning filter must be
changed regularly to maintain air
conditioning efficiency.
Removing the air conditioning
filter
A
B

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

4107-2. Steps to take in an emergency
If the engine coolant temperature
gauge enters the red zone or
“Engine Coolant Temp High Stop in
a Safe Place See Owner’s Manual”
is shown on the multi-information
display
1
Stop the vehicle in a safe place and
turn off the air conditioning system,
and then stop the hybrid system.
2
If you see steam:
Carefully lift the hood after the
steam subsides.
If you do not see steam:
Carefully lift the hood.
3
After the hybrid system has cooled
down sufficiently, inspect the hoses
WARNING
■When replacing the 12-volt battery
●When the vent plug is close to the hold
down clamp, the battery fluid (acid)
may leak.
●For information regarding battery
replacement, contact your Lexus
dealer.
●After exchanging, securely attach the
elbow connected to the exhaust hose,
and exhaust hole plug to the exhaust
hole of the exchanged 12-volt battery.
If not properly installed, gases (hydro-
gen) may leak into the vehicle interior,
and there is the possible danger of the
gas igniting and exploding.
NOTICE
■When handling jumper cables
When connecting the jumper cables,
ensure that they do not become entan-
gled in the cooling fans or belt.
■To prevent damaging the vehicle
The exclusive jump starting terminal is to
be used when charging the 12-volt bat-
tery from another vehicle in an emer-
gency. It cannot be used to jump start
another vehicle.
If your vehicle overheats
The following may indicate that
your vehicle is overheating.
 The engine coolant temperature
gauge ( P.78, 82) enters the
red zone, or a loss of hybrid sys-
tem power is experienced. (For
example, the vehicle speed does
not increase.)
 “Engine Coolant Temp High Stop
in a Safe Place See Owner’s
Manual” or “Hybrid system over-
heated Output power reduced” is
shown on the multi-information
display.
 Steam comes out from under the
hood.
Correction procedures

4117-2. Steps to take in an emergency
7
When trouble arises
and radiator core (radiator) for any
leaks.
Radiator
Cooling fans
If a large amount of coolant leaks, immedi-
ately contact your Lexus dealer.
4The coolant level is satisfactory if it
is between the “FULL” and “LOW”
lines on the reservoir.
Reservoir
“FULL” line
“LOW” line
5 Add coolant if necessary.
Water can be used in an emergency if coolant is unavailable.
6
Start the hybrid system and turn the
air conditioning system on to check
that the radiator cooling fans oper-
ate and to check for coolant leaks
from the radiator or hoses.
The fans operate when the air conditioning
system is turned on immediately after a
cold start. Confirm that the fans are oper-
ating by checking the fan sound and air
flow. If it is difficult to check these, turn the
air conditioning system on and off repeat-
edly.
(The fans may not oper ate in freezing tem-
peratures.)
7 If the fans are not operating:
Stop the hybrid system immediately
and contact your Lexus dealer.
If the fans are operating:
Have the vehicle inspected at the
nearest Lexus dealer.
8 Check if “Engine Coolant Temp
High Stop in a Safe Place See
Owner’s Manual” is shown on the
multi-information display.
If the message does not disappear:
Stop the hybrid system and contact
your Lexus dealer.
If the message is not displayed:
Have the vehicle inspected at the
nearest Lexus dealer.
A
B
A
B
C

4438-2. Customization
8
Vehicle specifications
■Intuitive parking assist* ( P.232)
*:If equipped
■RCTA (Rear Cross Traffic Alert) function* ( P.239)
*:If equipped
■PKSB (Parking Support Brake)* ( P.243)
*:If equipped
■Automatic air conditioning system ( P.276)
■Seat heater*/seat ventilators* ( P.286)
*:If equipped
FunctionDefault settingCustomized set-
ting
Intuitive parking assistOnOffO
FunctionDefault settingCustomized set-ting
RCTA (Rear Cross Traffic
Alert) functionOnOffO
FunctionDefault settingCustomized set-ting
PKSB (Parking Support Brake)
functionOnOffO
FunctionDefault settingCustomized set-ting
A/C auto switch operationOnOffOO
FunctionDefault settingCustomized set-ting
Driver’s seat temperature pref-
erence in automatic modeStandard-2 (cooler) to 2 (warmer)OO
Passenger’s seat temperature
preference in automatic modeStandard-2 (cooler) to 2 (warmer)OO
ABC
ABC
ABC
ABC
ABC

463Alphabetical Index
Alphabetical Index
A
A/C ....................................................................276Air conditioning filter ............................... 364
Automatic air conditioning system ... 276
ABS (Anti-lock Brake System).............. 256 Function .......................................................... 256
Warning light .............................................. 388
ACA (Active Cornering Assist) ........... 257
Active Cornering Assist (ACA) ........... 257
Active Sound Control (ASC) .................. 176
Airbags ................................................................. 31 Airbag operating conditions................... 33
Airbag precautions for your child ........ 36
Correct driving posture ............................ 25
Curtain shield airbag operating condi- tions .................................................................. 34
Curtain shield airbag precautions ....... 36
Front passenger occupant classification system ............................................................. 39
General airbag precautions ................... 36
Locations of airbags...................................... 31
Modification and disposal of airbags . 38
Side airbag operating conditions ......... 34
Side airbag precautions ............................ 36
Side and curtain shield airbags operating conditions...................................................... 34
Side and curtain shield airbags precau- tions .................................................................. 36
SRS airbags ....................................................... 31
SRS warning light ..................................... 388
Air conditioning filter ................................. 364
Air conditioning system .............................276 Air conditioning filter ............................... 364
Automatic air conditioning system ... 276
Alarm ..................................................................... 71 Warning buzzer .........................................386
Anchor brackets ..................................... 46, 54
Antennas (smart access system with push- button start) .................................................. 124
Anti-lock Brake System (ABS).............. 256 Function .......................................................... 256 Warning light .............................................. 388
Approach warning...................................... 222
Armrest............................................................. 310
ASC (Active Sound Control) .................. 176
Assist grips ........................................................ 311
Audio system-linked display ...................... 90
Automatic headlight leveling system ....178
Automatic High Beam ............................... 180
Automatic light control system................ 177
Average fuel economy................................. 89
Average vehicle speed ................................ 89
B
Back door .......................................................... 112 Hands Free Power Back Door ............. 116
Power back door.......................................... 115
Wireless remote control ......................... 106
Back-up lights Replacing light bulbs ................................ 374
Battery (12-volt battery) ........................... 342 Battery checking ........................................ 342
If the 12-volt battery is discharged ... 405
Preparing and checking before winter..........................................................................263
Replacing ...................................................... 408
Warning light .............................................. 386
Battery (traction batter y) ............................ 65
Blind Spot Monitor (BSM)....................... 226
Bottle holders ................................................ 295
Brake Brake Hold......................................................175
Fluid.....................................................................421
Parking brake ................................................ 172
Regenerative braking ................................. 63
Warning light .............................................. 386
Brake assist .................................................... 256
Brake Hold ....................................................... 175
Break-in tips.....................................................153
Brightness control Instrument panel light control....... 80, 86
BSM (Blind Spot Monitor)....................... 226

Alphabetical Index467
Glove box light ............................................. 294
Grocery bag hooks .................................... 296
H
Hands Free Power Back Door ................. 116
Headlights ........................................................ 177Automatic High Beam system............. 180
Light switch ..................................................... 177
Replacing light bulbs................................ 374
Headlights aim .............................................. 372
Head restraints ...............................................136
Head-up display.............................................. 93 Driving information display area........... 93
Driving support system display area .. 95
Head-up display switch............................. 94
Hybrid System Indicator ........................... 96
Navigation system-linked display ........ 93
Pop-up display............................................... 95
Settings .............................................................. 94
Head-up display switch................................ 94
Heated steering wheel .............................. 286
Heaters Automatic air conditioning system ... 276
Heated steering wheel............................286
Outside rear view mirrors .....................277
Seat heaters ..................................................286
Hill-start assist control ............................... 257
Hood ................................................................. 335 Open ............................................................... 335
Hooks Cargo hooks................................................ 296
Coat hooks .................................................... 310
Grocery bag hooks ................................. 296
Retaining hooks (floor mat)......................24
Horn ................................................................... 140
Hybrid battery (traction battery) Location............................................................. 65
Specification .................................................. 418
Warning message........................................ 68
Hybrid battery (traction battery) air vent ..............................................................................67
Hybrid system .................................................. 62 Emergency shut off system......................68
Energy monitor/consumption screen 97
EV drive mode............................................. 165
High voltage components .......................65
Hybrid system precautions......................65
Hybrid vehicle driving tips ......................261
If the hybrid system will not start ....... 400
Overheating .................................................. 410
Power (ignition) switch .............................162
Regenerative braking ................................. 63
Starting the hybrid system .......................162
Vehicle proximity noti
fication system. 64
Hybrid System Indicator..............79, 84, 96
Hybrid transmission...................................... 167
I
I/M test ..............................................................331
Identification Engine................................................................417
Vehicle ............................................................. 416
Ignition switch (Power switch) .................162 Auto power off function........................... 164
Changing the power switch modes . 164
If your vehicle has to be stopped in an emergency .................................................378
Starting the hybrid system .......................162
Illuminated entry system ........................... 290
Immobilizer system........................................ 69
Indicators ............................................................76
Initialization Items to initialize .........................................446
Maintenance.................................... 328, 339
Power windows ........................................... 145
Tire pressure warning system .............. 351
Inside rear view mirror ............................... 140
Instrument panel light control .......... 80, 86
Interior lights.................................................. 290
Intuitive parking assist...................... 231, 232 Function .......................................................... 232
Warning message ..................................... 234