tire LEXUS UX250H 2019 Repair Manual

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

3817-2. Steps to take in an emergency
7
When trouble arises
7-2.Steps to take in an emergency
If your vehicle needs to be
t
owed
If towing is ne cessary, we recom-
mend having your vehicle towed by
your Lexus dealer or commercial
towing service, using a wheel-lift
type truck or flatbed truck.
Use a safety chain system for all
towing, and abide by all state/pro-
vincial and local laws.
2WD models: If towing your vehicle
with a wheel-lift type truck from the
front, the vehicle’s rear wheels and
axles must be in good conditions.
(  P.381, 383) If they are dam-
aged, use a towing dolly or flatbed
truck.
AWD models: If towing your vehi-
cle with a wheel-lift type truck, use
a towing dolly. ( P.381, 383)
WARNING
Observe the following precautions.
Failure to do so may result in death or
serious injury.
■When towing the vehicle
2WD models
Be sure to transport the vehicle with the
front wheels raised or with all four wheels
raised off the ground. If the vehicle is
towed with the front wheels contacting
the ground, the drivetrain and related
parts may be damaged or electricity
generated by the operation of the motor
may cause a fire to occur depending on
the nature of the damage or malfunction.
AWD models
Be sure to transport the vehicle with all
four wheels raised off the ground. If the
vehicle is towed with the tires contacting
the ground, the driv etrain or related
parts may be damaged, the vehicle may
fly off the truck, or electricity generated
by the operation of the motor may cause
a fire to occur depending on the nature
of the damage or malfunction.

3857-2. Steps to take in an emergency
7
When trouble arises
Fluid leaks under the vehicle
(Water dripping from the air condi-
tioning after use is normal.)
 Flat-looking tires or uneven tire
wear
 Engine coolant temperature gauge
needle continually points higher
than normal
 Changes in exhaust sound
 Excessive tire squeal when corner-
ing
 Strange noises related to the sus-
pension system
 Pinging or other noises related to
the hybrid system
 Engine missing, stumbling or run-
ning roughly
 Appreciable loss of power
 Vehicle pulls heavily to one side
when braking 
Vehicle pulls heavily to one side
when driving on a level road
 Loss of brake effectiveness, spongy
feeling, pedal almost touches the
floor
If you think something is
wrong
If you notice any of the following
symptoms, your vehicle probably
needs adjustment or repair. Con-
tact your Lexus dealer as soon as
possible.
Visible symptoms
Audible symptoms
Operational symptoms

3877-2. Steps to take in an emergency
7
When trouble arises
■Malfunction indicator lamp (warning buzzer)
■High coolant temperature warning light* (warning buzzer)
*: This light illuminates on the multi-information display.
■Tire pressure warning light
■Brake system warning light (warning buzzer)
Warning lightDetails/Actions
(U.S.A.)
or
(Canada)
Indicates a malfunction in:
The hybrid system;
 The electronic engine control system; or
 The electronic throttle control system
 Immediately stop the vehicle in a safe place and contact your Lexus
dealer.
Warning lightDetails/Actions
Indicates that the engine coolant temperature is too high
 Immediately stop the vehicle in a safe place.
Handling method ( P.410)
Warning lightDetails/Actions
When the light comes on after bl inking for approximately 1 minute:
Malfunction in the tire pressure warning system
 Have the system checked by your Lexus dealer.
When the light comes on:
Low tire inflation pressure such as
 Natural causes
 Flat tire
 P.393
Warning lightDetails/Actions
(yellow)
Indicates a malfunction in:
The regenerative braking system;
 The electronically controlled brake system; or
 The parking brake system
 Have the vehicle inspected by your Lexus dealer immediately.

3937-2. Steps to take in an emergency
7
When trouble arises
bag sensor assembly, front impact sensors,
side impact sensors (front door), side
impact sensors (front), side impact sensors
(rear), driver’s seat position sensor, driver’s
seat belt buckle switch, front passenger
occupant classification system (ECU and
sensors), rear seat belt buckle switches (if
equipped), “AIR BAG ON” indicator light,
“AIR BAG OFF” indicator light, front pas-
senger’s seat belt buckle switch, seat belt
pretensioners, airbags, interconnecting wir-
ing and power sources. (P.31)
■Electric power steering system warning
light (warning buzzer)
When the 12-volt battery charge becomes
insufficient or the voltage temporarily
drops, the electric po wer steering system
warning light may come on and the warning
buzzer may sound.
■When the tire pressure warning light
comes on
Inspect the tires to check if a tire is punc-
tured.
If a tire is punctured: P.399
If none of the tires are punctured:
Turn the power switch off then turn it to ON.
Check if the tire pressure warning light
comes on or blinks.
If the tire pressure warning light blinks for
approximately 1 minute then stays on
There may be a malfunction in the tire pres-
sure warning system. Have the vehicle
inspected by your Lexus dealer immedi-
ately.
If the tire pressure warning light comes
on
1
After the temperature of the tires has
lowered sufficiently, check the inflation
pressure of each tire and adjust them to
the specified level.
2
If the warning light does not turn off
even after several minutes have
elapsed, check that the inflation pres-
sure of each tire is at the specified level
and perform initialization. ( P.351)
■The tire pressure warning light may
come on due to natural causes
The tire pressure warning light may come
on due to natural causes such as natural air leaks and tire inflation pressure changes
caused by temperature. In this case, adjust-
ing the tire inflation pressure will turn off the
warning light (after a few minutes).
■Conditions that the tire pressure warn-
ing system may not function properly
 P.348
WARNING
■If both the ABS and the brake system
warning lights remain on
Stop your vehicle in a safe place immedi-
ately and contact your Lexus dealer.
The vehicle will become extremely
unstable during braking, and the ABS
system may fail, which could cause an
accident resulting in death or serious
injury.
■When the electric power steering
system warning light comes on
When the light comes on yellow, the
assist to the power st eering is restricted.
When the light comes on red, the assist
to the power steering is lost and handling
operations of the steering wheel become
extremely heavy.
When steering wheel operations are
heavier than usual, grip the steering
wheel firmly and operate it using more
force than usual.
■If the tire pressure warning light
comes on
Be sure to observe the following precau-
tions.
Failure to do so could cause a loss of
vehicle control and result in death or
serious injury.
●Decelerate to the lowest appropriate
speed as soon as possible. Do not
drive over 50 mph (80 km/h).
●Check and adjust the tire inflation
pressure immediately.

3947-2. Steps to take in an emergency
WARNING
●If the tire pressure warning light comes
on even after tire inflation pressure
adjustment, it is probable that you have
a flat tire. Have the flat tire replaced by
the nearest Lexus dealer.
●Avoid abrupt maneuvering and brak-
ing.
If the vehicle tires deteriorate, you
could lose control of the steering
wheel or the brakes.
■If a blowout or sudden air leakage
should occur
The tire pressure warning system may
not activate immediately.
■Maintenance of the tires
Each tire, including the spare (if pro-
vided), should be checked monthly when
cold and inflated to the inflation pressure
recommended by the vehicle manufac-
turer on the vehicle placard or tire infla-
tion pressure label (tire and load
information label). (If your vehicle has
tires of a different size than the size indi-
cated on the vehicle placard or tire infla-
tion pressure label [tire and load
information label], yo u should determine
the proper tire infl ation pressure for
those tires.)
As an added safety feature, your vehicle
has been equipped with a tire pressure
monitoring system (TPMS-tire pressure
warning system) that illuminates a low
tire pressure telltale (tire pressure warn-
ing light) when one or more of your tires
is significantly under-inflated. Accord-
ingly, when the low tire pressure telltale
(tire pressure warnin g light) illuminates,
you should stop and check your tires as
soon as possible, and inflate them to the
proper pressure. Driving on a signifi-
cantly under-inflated tire causes the tire
to overheat and can lead to tire failure.
Under-inflation also reduces fuel effi-
ciency and tire tread life, and may affect
the vehicle’s handling and stopping abil-
ity.
Please note that the TPMS (tire pressure
warning system) is not a substitute for
proper tire maintenance, and it is the
driver’s responsibility to maintain correct
tire pressure, even if under-inflation has
not reached the level to trigger illumina-
tion of the TPMS low tire pressure telltale
(tire pressure warning light).
Your vehicle has also been equipped with
a TPMS (tire pressure warning system)
malfunction indicator to indicate when
the system is not operating properly. The
TPMS (tire pressure warning system)
malfunction indicator is combined with
the low tire pressure telltale (tire pres-
sure warning light) . When the system
detects a malfunction, the telltale will
flash for approximately one minute and
then remain continuously illuminated.
This sequence will continue upon subse-
quent vehicle start-ups as long as the
malfunction exists. When the malfunction
indicator is illuminated, the system may
not be able to detect or signal low tire
pressure as intended.
TPMS (tire pressure warning system)
malfunctions may occur for a variety of
reasons, including the installation of
replacement or alternate tires or wheels
on the vehicle that prevent the TPMS
(tire pressure warning system) from func-
tioning properly. Always check the
TPMS (tire pressure warning system)
malfunction telltale after replacing one
or more tires or wheels on your vehicle to
ensure that the replacement or alternate
tires and wheels allow the TPMS (tire
pressure warning system) to continue to
function properly.
NOTICE
■To ensure the tire pressure warning
system operates properly
Do not install tires with different specifi-
cations or makers, as the tire pressure
warning system may not operate prop-
erly.

3997-2. Steps to take in an emergency
7
When trouble arises
form the procedure on P.365 to clean
them.
• If the warning message is shown when
the air intake vent and filter of the hybrid
battery (traction battery) are not dirty,
have the vehicle inspected by your Lexus
dealer.
Take your vehicle to the nearest Lexus
dealer or authorized tire dealer as
soon as possible if any tire goes flat.
The vehicle can be driven for a maximum
of 100 miles (160 km) at a speed below 50
mph (80 km/h) after the tire pressure
warning light comes on. ( P.387)
A run-flat tire has a mark on the
side wall.
■In some condition (such as at high tem-
peratures)
You cannot continue dr iving for up to 100
miles (160 km).
■For the detailed information on run-flat
tires
 P.347
NOTICE
■If “High Power Consumption Power
to Climate Temporarily Limited” is
displayed frequently
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.
■If “Low Auxiliary Battery” is displayed
frequently
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 not equipped with a
spare tire, but instead you can con-
tinue driving the vehicle with run-
flat tires even if any tire goes flat.
In this case, slow down and drive
with extra caution.
Run-flat tires

4007-2. Steps to take in an emergency
One of the following may be the cause
of the problem:
The electronic key may not be func-
tioning properly. ( P.403)
 There may not be sufficient fuel in
the vehicle’s tank.
Refuel the vehicle. ( P.190)
 There may be a malfunction in the
immobilizer system. ( P.69)
 There may be a malfunction in the
steering lock system.
 The hybrid system may be malfunc-
tioning due to an electrical problem
such as electronic key battery
depletion or a blown fuse. However,
depending on the type of malfunc-
tion, an interim measure is available
to start the hybrid system.
One of the following may be the cause
NOTICE
■When replacing the tires
When removing or fitting the wheels,
tires or the tire pressure warning valve
and transmitter, contact your Lexus
dealer as the tire pr essure warning valve
and transmitter may be damaged if not
handled correctly.
■When driving over bumps
If a vehicle has a flat tire, the vehicle
height will be lower than usual. Ensure
that nothing strikes the bottom of the
vehicle.
■To avoid damaging 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. Make sure to replace
the tire pressure warning valve and trans-
mitter when replacing the tire. ( P.350)
If the hybrid system will not
s
tart
Reasons for the hybrid system not
starting vary depending on the situ-
ation. Check the following and per-
form the appropriate procedure:
The hybrid system will not start
even though the correct starting
procedure is being followed.
(  P.162)
The interior lights and head-
lights are dim, or the horn does
not sound or sounds at a low vol-
ume.

4137-2. Steps to take in an emergency
7
When trouble arises
1Stop the hybrid system. Shift the
shift lever to P and set the parking
brake.
2
Remove the mud, snow or sand
from around the front wheels.
3
Place wood, stones or some other
material under the front wheels to
help provide traction.
4
Restart the hybrid system.
5
Shift the shift lever to D or R and
release the parking brake. Then,
while exercising caution, depress
the accelerator pedal.
■When it is difficult to free the vehicle
Press the switch to turn off TRAC.
(  P.257)
WARNING
●After the hybrid system has been
turned off, check that the “READY”
indicator is off. When the hybrid sys-
tem is operating, the gasoline engine
may automatically start, or the cooling
fan may suddenly operate even if the
gasoline engine stops. Do not touch or
approach rotating parts such as the
fan, which may lead to fingers or cloth-
ing (especially a tie, a scarf or a muf-
fler) getting caught, resulting in serious
injury.
●Do not loosen the coolant reservoir
cap while the hybrid system and radia-
tor are hot.
High temperature steam or coolant
could spray out.
NOTICE
■When adding engine/power control
unit coolant
Add coolant slowly after the hybrid sys-
tem has cooled down sufficiently. Adding
cool coolant to a hot hybrid system too
quickly can cause damage to the hybrid
system.
■To prevent damage to the cooling sys-
tem
Observe the following precautions:
●Avoid contaminating the coolant with
foreign matter (such as sand or dust
etc.).
●Do not use any coolant additive.
If the vehicle becomes stuck
Carry out the following proce-
dures if the tires spin or the vehicle
becomes stuck in mud, dirt or snow:
Recovering procedure

4147-2. Steps to take in an emergency
WARNING
■When attempting to free a stuck vehi-
cle
If you choose to push the vehicle back
and forth to free it, make sure the sur-
rounding area is clear to avoid striking
other vehicles, objects or people. The
vehicle may also lunge forward or lunge
back suddenly as it becomes free. Use
extreme caution.
■When shifting the shift lever
Be careful not to shif t the shift lever with
the accelerator pedal depressed.
This may lead to unexpected rapid accel-
eration of the vehicle that may cause an
accident resulting in death or serious
injury.
NOTICE
■To avoid damage to the hybrid trans-
mission and other components
●Avoid spinning the tires and depress-
ing the accelerator pedal more than
necessary.
●If the vehicle remains stuck even after
these procedures are performed, the
vehicle may require towing to be freed.