Lexus CT (2021 year). Manual in english — page 30

612

7-3. Do-it-yourself maintenance

Your vehicle is equipped with a tire pressure warning system that uses tire pres-
sure warning valves and transmitters 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
warning light. (



P. 668)

◆

Installing tire pressure warning valves and transmitters

When replacing tires or wheels, tire pressure warning valves and transmitters
must also be installed.
When new tire pressure warning valves and transmitters are installed, new ID
codes must be registered in the tire pressure warning computer and the tire
pressure warning system must be initialized. Have tire pressure warning valve
and transmitter ID codes registered by any authorized Lexus retailer or Lexus
authorized repairer, or any reliable repairer. (



P. 613)

◆

Initializing the tire pressure warning system

■

The tire pressure warning system must be initialized in the following circum-
stances:

●

Vehicles with 17 inch tires: When rotating front and rear tires which have
different tire inflation pressures

●

When the tire inflation pressure is changed such as when changing travel-
ing speed or load weight.

●

When changing the tire size

When the tire pressure warning system is initialized, the current tire inflation
pressure is set as the benchmark pressure.

■

How to initialize the tire pressure warning system

Park the vehicle in a safe place and turn the power switch off.

Initialization cannot be performed while the vehicle is moving.

Adjust the tire inflation pressure to the specified cold tire inflation pressure
level. (



P. 738)

Make sure to adjust the tire pressure to the specified cold tire inflation pressure

level. The tire pressure warning system will operate based on this pressure level.

Tire pressure warning system

1

2

613

7-3. Do-it-yourself maintenance

7

M

ain

te

na

nce an

d

ca

re

Turn the power switch to ON mode.
Press and hold the tire pressure
warning reset switch until the tire
pressure warning light blinks
slowly 3 times.

Wait for a few minutes with the power switch in ON mode and then turn
the power switch off.

◆

Registering ID codes

The tire pressure warning valve and transmitter is equipped with a unique ID
code. When replacing a tire pressure warning valve and transmitter, it is nec-
essary to register the ID code. Have the ID code registered by any authorized
Lexus retailer or Lexus authorized repairer, or any reliable repairer.

■

When to replace your vehicle’s tires

Tires should be replaced if:

●

The treadwear indicators are showing on a tire.

●

You have tire damage such as cuts, splits, cracks deep enough to expose the fabric, and

bulges indicating internal damage.

●

A tire goes flat repeatedly or cannot be properly repaired due to the size or location of

a cut or other damage.

If you are not sure, consult with any authorized Lexus retailer or Lexus authorized

repairer, or any reliable repairer.

■

Replacing 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 10 minutes, the

tire pressure warning light blinks for 1 minute and stays on to indicate a system malfunc-

tion.

■

Tire life

Any tire over 6 years old must be checked by a qualified technician even if it has seldom

or never been used or damage is not obvious.

3

4

5

614

7-3. Do-it-yourself maintenance

■

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.

■

Low profile tires (vehicles with 17 inch tires)

Generally, low profile tires will wear more rapidly and tire grip performance will be

reduced on snowy and/or icy roads when compared to standard tires. Be sure to use

snow tires or tire chains on snowy and/or icy roads and drive carefully at a speed appro-

priate for road and weather conditions.

■

If the tread on snow tires wears down below 4 mm (0.16 in.)

The effectiveness of the tires as snow tires is lost.

■

Situations in which the tire pressure warning system may not operate properly

●

In the following cases, the tire pressure warning system may not operate properly.
• 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 vehicle, particularly around the wheels or wheel

housings.

• If the tire inflation pressure is extremely higher than the specified level.

• If wheel without the tire pressure warning valve and transmitter is used.

• If the ID code on the tire pressure warning valves and transmitters is not registered

in the tire pressure warning computer.

●

Performance may be affected in the following situations.
• Near a TV tower, electric power plant, gas station, radio station, large display, air-

port or other facility that generates strong radio waves or electrical noise

• When carrying a portable radio, cellular phone, cordless phone or other wireless

communication device

●

When the vehicle is parked, the time taken for the warning to start or go off could be

extended.

●

When tire inflation pressure declines rapidly for example when a tire has burst, the

warning may not function.

■

The initialization operation

●

Make sure to carry out initialization after adjusting the tire inflation pressure.

Also, make sure the tires are cold before carrying out initialization or tire inflation pres-

sure adjustment.

●

If you have accidentally turned the power switch off during initialization, it is not neces-

sary to press the reset switch again as initialization will restart automatically when the

power switch has been turned to ON mode for the next time.

●

If you accidentally press the reset switch when initialization is not necessary, adjust the

tire inflation pressure to the specified level when the tires are cold, and conduct initial-

ization again.

615

7-3. Do-it-yourself maintenance

7

M

ain

te

na

nce an

d

ca

re

■

Warning performance of the tire pressure warning system

The warning of the tire pressure warning system will change in accordance with the con-

ditions under which it was initialized. For this reason, the system may give a warning even

if the tire pressure does not reach a low enough level, or if the pressure is higher than the

pressure that was adjusted to when the system was initialized.

■

When initialization of the tire pressure warning system has failed

Initialization can be completed in a few minutes. However, in the following cases, the set-

tings have not been recorded and the system will not operate properly. If repeated

attempts to record tire inflation pressure settings are unsuccessful, have the vehicle

inspected by any authorized Lexus retailer or Lexus authorized repairer, or any reliable

repairer.

●

When operating the tire pressure warning reset switch, the tire pressure warning light

does not blink 3 times.

●

After carrying out the initialization procedure, the tire pressure warning light blinks for 1

minute then stays on after driving for 20 minutes.

628

7-3. Do-it-yourself maintenance

WARNING

■

When inspecting or replacing tires

Observe the following precautions to prevent accidents.

Failure to do so may cause damage to parts of the drive train as well as dangerous han-

dling characteristics, which may lead to an accident resulting in death or serious injury.

●

Make sure to install four tires that are of the specified size, and that all four tires are of

the same size, same brand, and same tread pattern.

●

Do not use tire sizes other than those recommended by Lexus.

●

Do not mix differently constructed tires (radial, bias-belted or bias-ply tires).

●

If only two tires are replaced, the new tires should be placed on the rear of the vehicle.

●

Do not mix summer, all season and snow tires.

●

Do not use tires that have been used on another vehicle.

Do not use tires if you do not know how they were used previously.

●

Vehicles with a compact spare tire: Do not tow if your vehicle has a compact spare

tire installed.

●

Vehicles with an emergency tire puncture repair kit: Do not tow anything if a tire that

has been repaired using the emergency tire puncture repair kit is installed. The load

on the tire may cause unexpected damage to the tire.

■

When initializing the tire pressure warning system

Do not operate the tire pressure warning reset switch without first adjusting the tire

inflation pressure to the specified level. Otherwise, the tire pressure warning light may

not come on even if the tire inflation pressure is low, or it may come on when the tire

inflation pressure is actually normal.

629

7-3. Do-it-yourself maintenance

7

M

ain

te

na

nce an

d

ca

re

NOTICE

■

Repairing or replacing tires, wheels, tire pressure warning valves, transmitters and

tire valve caps

●

When removing or fitting the wheels, tires or the tire pressure warning valves and

transmitters, contact any authorized Lexus retailer or Lexus authorized repairer, or

any reliable repairer as the tire pressure warning valves and transmitters may be dam-

aged 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.

■

To avoid damage to the tire pressure warning valves and transmitters

When a tire is repaired with liquid sealants, the tire pressure warning valve and trans-

mitter may not operate properly. If a liquid sealant is used, contact any authorized

Lexus retailer or Lexus authorized repairer, or any reliable repairer or other qualified

service shop as soon as possible. After use of liquid sealant, make sure to replace the

tire pressure warning valve and transmitter when repairing or replacing the tire.

(



P. 612)

■

Driving on rough roads

Take particular care when driving on roads with loose surfaces or potholes.

These conditions may cause losses in tire inflation pressure, reducing the cushioning

ability of the tires. In addition, driving on rough roads may cause damage to the tires

themselves, as well as the vehicle’s wheels and body.

■

Low profile tires (vehicles with 17 inch tires)

Low profile tires may cause greater damage than usual to the tire wheel when sustain-

ing impact from the road surface. Therefore, pay attention to the following:

●

Be sure to use proper tire inflation pressure. If tires are under-inflated, they may be

damaged more severely.

●

Avoid potholes, uneven pavement, curbs and other road hazards. Failure to do so

may lead to severe tire and wheel damage.

■

If tire inflation pressure of each tire becomes low while driving

Do not continue driving, or your tires and/or wheels may be ruined.

630

7-3. Do-it-yourself maintenance

Tire inflation pressure

■

Effects of incorrect tire inflation pressure

Driving with incorrect tire inflation pressure may result in the following:

●

Reduced fuel economy

●

Reduced driving comfort and poor handling

●

Reduced tire life due to wear

●

Reduced safety

●

Damage to the drive train

If a tire needs frequent inflating, have it checked by any authorized Lexus retailer or

Lexus authorized repairer, or any reliable repairer.

■

Instructions for checking tire inflation pressure

When checking tire inflation pressure, observe the following:

●

Check only when the tires are cold.

If your vehicle has been parked for at least 3 hours or has not been driven for more than

1.5 km or 1 mile, you will get an accurate cold tire inflation pressure reading.

●

Always use a tire pressure gauge.

It is difficult to judge if a tire is properly inflated based only on its appearance.

●

It is normal for the tire inflation pressure to be higher after driving as heat is generated

in the tire. Do not reduce tire inflation pressure after driving.

●

Passengers and luggage weight should be placed so that the vehicle is balanced.

Make sure to maintain proper tire inflation pressure. Tire inflation pressure
should be checked at least once per month. However, Lexus recommends
that tire inflation pressure be checked once every two weeks. (



P. 738)

WARNING

■

Proper inflation is critical to save tire performance

Keep your tires properly inflated.
If the tires are not properly inflated, the following conditions may occur which could

lead to an accident resulting in death or serious injury:

●

Excessive wear

●

Uneven wear

●

Poor handling

●

Possibility of blowouts resulting from overheated tires

●

Air leaking from between tire and wheel

●

Wheel deformation and/or tire damage

●

Greater possibility of tire damage while driving (due to road hazards, expansion

joints, sharp edges in the road, etc.)

631

7-3. Do-it-yourself maintenance

7

M

ain

te

na

nce an

d

ca

re

NOTICE

■

When inspecting and adjusting tire inflation pressure

Be sure to put the tire valve caps back on.

If a valve cap is not installed, dirt or moisture may get into the valve and cause an air

leak, resulting in decreased tire inflation pressure.

632

7-3. Do-it-yourself maintenance

Wheels

When replacing wheels, care should be taken to ensure that they are equivalent
to those removed in load capacity, diameter, rim width and inset

*

.

Replacement wheels are available at any authorized Lexus retailer or Lexus
authorized repairer, or any reliable repairer.

*

: Conventionally referred to as “offset”.

Lexus does not recommend using the following:

●

Wheels of different sizes or types

●

Used wheels

●

Bent wheels that have been straightened

●

Use only Lexus wheel nuts and wrenches designed for use with your alumi-
num wheels.

●

When rotating, repairing or changing your tires, check that the wheel nuts are
still tight after driving 1600 km (1000 miles).

●

Be careful not to damage the aluminum wheels when using tire chains.

●

Use only Lexus genuine balance weights or equivalent and a plastic or rubber
hammer when balancing your wheels.

■

When replacing wheels

The wheels of your vehicle are equipped with tire pressure warning valves and transmit-

ters that allow the tire pressure warning system to provide advance warning in the event

of a loss in tire inflation pressure. Whenever wheels are replaced, tire pressure warning

valves and transmitters must be installed. (



P. 612)

If a wheel is bent, cracked or heavily corroded, it should be replaced. Other-
wise, the tire may separate from the wheel or cause a loss of handling control.

Wheel selection

Aluminum wheel precautions

633

7-3. Do-it-yourself maintenance

7

M

ain

te

na

nce an

d

ca

re

WARNING

■

When replacing wheels

●

Do not use wheels that are a different size from those recommended in the Owner’s

Manual, as this may result in a loss of handling control.

●

Never use an inner tube in a leaking wheel which is designed for a tubeless tire. Doing

so may result in an accident, causing death or serious injury.

■

Use of defective wheels prohibited

Do not use cracked or deformed wheels.

Doing so could cause the tire to leak air during driving, possibly causing an accident.

NOTICE

■

Replacing tire pressure warning valves and transmitters

●

Because tire repair or replacement may affect the tire pressure warning valves and

transmitters, make sure to have tires serviced by any authorized Lexus retailer or

Lexus authorized repairer, or any reliable repairer or other qualified service shop. In

addition, make sure to purchase your tire pressure warning valves and transmitters at

any authorized Lexus retailer or Lexus authorized repairer, or any reliable repairer.

●

Ensure that only genuine Lexus wheels are used on your vehicle.

Tire pressure warning valves and transmitters may not work properly with non-genu-

ine wheels.

634

7-3. Do-it-yourself maintenance

Air conditioning filter

Turn the power switch off.
Open the glove box. Lift and remove
the partition.

Remove the glove box cover.

Remove the filter cover.

The air conditioning filter must be cleaned or changed regularly to maintain
air conditioning efficiency.

Removal method

1

2

3

4

635

7-3. Do-it-yourself maintenance

7

M

ain

te

na

nce an

d

ca

re

Slide and pull out the filter. Replace it
with a new one.

The “



UP” marks shown on the filter

should be pointing up.

If the filter is dirty, clean by blowing
compressed air through the filter from
the underside.

Hold the air gun 5 cm (2 in.) from the fil-

ter and blow for approximately 2 min-

utes at 500 kPa (5.0 kgf/cm

2

or bar, 72

psi).
If an air gun is not available, have the fil-

ter cleaned by any authorized Lexus

retailer or Lexus authorized repairer, or

any reliable repairer.

■

Checking interval

Inspect, clean and replace the air conditioning filter 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 “Lexus Service

Booklet” or “Lexus Warranty Booklet”.)

■

If air flow from the vents decreases dramatically

The filter may be clogged. Check the filter and replace if necessary.

5

Cleaning method

NOTICE

■

To prevent damage to the system

●

When using the air conditioning system, make sure that a filter is always installed.

●

When cleaning the filter, do not clean with water.

636

7-3. Do-it-yourself maintenance

Electronic key battery

●

Flathead screwdriver

●

Small Phillips-head screwdriver

●

Lithium battery CR1632



Type A
Take out the mechanical key.
(



P. 119)

Remove the cover.

Remove the battery cover bolts and
remove the battery cover.

Replace the battery with a new one if it is depleted.

You will need the following items:

Replacing the battery

1

2

3

637

7-3. Do-it-yourself maintenance

7

M

ain

te

na

nce an

d

ca

re

Remove the depleted battery.

Insert a new battery with the “+” termi-

nal facing up.



Type B
Take out the mechanical key.
(



P. 119)

Remove the cover.

To prevent damage to the key, cover the

tip of the screwdriver with a rag.

Remove the depleted battery.

Insert a new battery with the “+” termi-

nal facing up.

4

1

2

3

638

7-3. Do-it-yourself maintenance

■

Use a CR1632 lithium battery

●

Batteries can be purchased at any authorized Lexus retailer or Lexus authorized

repairer, or any reliable repairer, 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.

■

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.

■

If the electronic key battery is depleted

The following symptoms may occur:

●

The smart entry & start system and wireless remote control will not function properly.

●

The operational range will be reduced.

WARNING

■

Battery precautions

Observe the following precautions. Failure to do so may result in death or serious

injury.

●

Do not swallow the battery. Doing so may cause chemical burns.

●

A coin battery or button battery is used in the electronic key. If a battery is swallowed,

it may cause severe chemical burns in as little as 2 hours and may result in death or

serious injury.

●

Keep away new and removed batteries from children.

●

If the cover cannot be firmly closed, stop using the electronic key and stow the key in

the place where children cannot reach, and then contact any authorized Lexus

retailer or Lexus authorized repairer, or any reliable repairer.

●

If you accidentally swallow a battery or put a battery into a part of your body, get

emergency medical attention immediately.

■

To prevent battery explosion or leakage of flammable liquid or gas

●

Replace the battery with a new battery of the same type. If a wrong type of battery is

used, it may explode.

●

Do not expose batteries to extremely low pressure due to high altitude or extremely

high temperatures.

●

Do not burn, break or cut a battery.

■

Certification for the smart entry & start system

CAUTION

RISK OF EXPLOSION IF BATTERY IS REPLACED BY AN INCORRECT TYPE.

DISPOSE OF USED BATTERIES ACCORDING TO THE INSTRUCTIONS

639

7-3. Do-it-yourself maintenance

7

M

ain

te

na

nce an

d

ca

re

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 component inside the remote control.

●

Do not bend either of the battery terminals.