inflation pressure Lexus IS250C 2012 Instrument cluster / LEXUS 2012 IS250C,IS350C (OM53A62U) Owner's Manual

5
When trouble arises
499
5-2. Steps to take in an emergency
■If the malfunction indicator lamp comes on while driving
First check the following:
●Is the fuel empty?
If it is, fill the fuel tank immediately.
●Is the fuel tank cap loose?
If it is, tighten it securely.
The lamp will go off after taking several driving trips.
If the lamp does not go off even after several trips, contact your Lexus dealer as
soon as possible.
■Electric power steering system warning light
When the voltage is low or drops, the electric power steering system warning light
may come on.
■Front passenger detection se nsor and passenger seat belt reminder and warning
buzzer
●If luggage is placed on the front passenger seat, the front passenger detection
sensor may cause the warning light to flash and the warning buzzer to sound,
even if a passenger is not sitting in the seat.
●If a cushion is placed on the seat, the sensor may not detect a passenger, and the
warning light may not operate properly.
■When the tire pressure warning light comes on
Check the tire inflation pressure and adjust to the appropriate level. Pressing the
satellite switch does not turn off the tire pressure warning light.

500
5-2. Steps to take in an emergency
■The tire pressure warning light may turn on due to natural causes
The tire pressure warning light may turn on due to natural causes such as natural air
leaks or 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).
■When a tire is replaced with a spare tire (vehicles with a spare tire)
The compact spare tire is not equipped wi th the tire pressure warning valve and
transmitter. If a tire goes flat, the tire pressure warning light will not turn off even
though the flat tire is replaced with the spare tire. Replace the spare tire with the
repaired tire and adjust the proper tire inflation pressure. The tire pressure warning
light will turn off after a few minutes.
■If the tire pressure warning system is inoperative
The tire pressure warning system will be disabled in the following conditions:
(When the condition becomes normal, the system will work properly.)
●If tires not equipped with tire pressure warning valves and transmitters are used
●If the ID code on the tire pressure warning valves and transmitters is not regis-
tered in the tire pressure warning computer
●If a different set of tires has been selected using the satellite switch.
●If the tire inflation pressure is 73 psi (500 kPa, 5.1 kgf/cm2 or bar) or higher
The tire pressure warning system may be disabled in the following conditions:
(When the condition becomes normal, the system will work properly.)
●If electronic devices or facilities using similar radio wave frequencies are nearby
●If a radio set at similar frequencies is in use in the vehicle
●If there is a lot of snow or ice on the vehicle, in particular around the wheels or
wheel housings
●If non-genuine Lexus wheels are used (Even if you use Lexus wheels, the tire
pressure warning system may not work properly with some types of tires.)
●If tire chains are used
■If the tire pressure warning light freque ntly comes on after blinking for 1 minute
If the tire pressure warning light frequently comes on after blinking for 1 minute
when the “ENGINE START STOP” switch is turned to IGNITION ON mode, have
it checked by your Lexus dealer.

5
When trouble arises
501
5-2. Steps to take in an emergency
■If the open retractable hardtop warning buzzer sounds
Immediately stop the vehicle in a safe place and open or close the retractable hard-
top fully.
CAUTION
■When the electric power steering system warning light comes on
The steering wheel may become extremely heavy.
If the steering wheel becomes heavier than usual when operating, hold firmly and
operate using more force than usual.
■If the tire pressure warning light comes on
Be sure to observe the following precautions. Failure to do so could cause loss of
vehicle control and result in death or serious injury.
Vehicles with run-flat tires
• 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.
• 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 tire replaced by
the nearest Lexus dealer.
• Avoid abrupt maneuvering and braking. If the vehicle tires deteriorate, you
could lose control of the steering wheel or the brakes.
Vehicles with standard tires
• Stop your vehicle in a safe place as soon as possible. Adjust the tire inflation pressure immediately.
• If the tire pressure warning light comes on even after tire inflation pressure adjustment, it is probable that you have a flat tire. Check the tires. If the tire is
flat, change to the spare tire and have the flat tire repaired by the nearest
Lexus dealer.
• Avoid abrupt maneuvering and braking. 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.

502
5-2. Steps to take in an emergency
CAUTION
■Maintenance of the tires
Each tire, including the spare (if provided), should be checked monthly when cold
and inflated to the inflation pressure re commended by the vehicle manufacturer on
the vehicle placard or tire inflation pressu re label (tire and load information label).
(If your vehicle has tires of a different size than the size indicated on the vehicle
placard or tire inflation pressure label [tire and load information label], you should
determine the proper tire inflation pressure for those tires.)
As an added safety feature, your vehicl e has been equipped with a tire pressure
monitoring system (TPMS-tire pressure warning system) that illuminates a low tire
pressure telltale (tire pressure warning light) when one or more of your tires is sig-
nificantly under-inflated. Accordingly, when the low tire pressure telltale (tire pres-
sure warning light) illuminates, you should stop and check your tires as soon as
possible, and inflate them to the proper pressure. Driving on a significantly under-
inflated tire causes the tire to overheat and can lead to tire failure. Under-inflation
also reduces fuel efficiency and tire tread life, and may affect the vehicle's handling
and stopping ability.
Please note that the TPMS (tire pressure warning system) is not a substitute for
proper tire maintenance, and it is the driv er's responsibility to maintain correct tire
pressure, even if under-inflation has not reached the level to trigger illumination 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 th e system is not operating properly. The
TPMS (tire pressure warning system) malfunction indicator is combined with the
low tire pressure telltale (tire pressure 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 subsequent vehicle
start-ups as long as the malfunction exists . When the malfunction indicator is illumi-
nated, 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 rea-
sons, including the installation of replacem ent or alternate tires or wheels on the
vehicle that prevent the TPMS (tire pres sure warning system) from functioning
properly. Always check the TPMS (tire pressure warning system) malfunction tell-
tale 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.

5
When trouble arises
523
5-2. Steps to take in an emergency
■The compact spare tire
●The compact spare tire is identified by the label “TEMPORARY USE ONLY”
on the tire sidewall.
Use the compact spare tire temporarily only in an emergency.
●Make sure to check the tire pressure of the compact spare tire. (P. 5 7 2 )
■When using the compact spare tire
As the compact spare tire is not equipped with the tire pressure warning valve and
transmitter, low inflation pressure of the spare tire will not be warned. Also, if you
replace the compact spare tire after the tire pressure warning light comes on, the
light remains on.
■If you have a flat rear tire on a road covered with snow or ice
Install the compact spare tire on the front of the vehicle. Perform the following steps
and fit tire chains to the rear tires.
Replace a front tire with the compact spare tire.
Replace the flat rear tire with the tire removed from the front of the vehi-
cle.
Fit tire chains to the rear tires.
■After completing the tire change
The tire pressure warning system must be reset. ( P. 4 3 8 )
STEP1
STEP2
STEP3

572
6-1. Specifications
Steering
Tires and wheelsTy p e A
Free playLess than 1.2 in. (30 mm)
Ti r e s i z e
Front tires: 225/45R17 90W
Rear tires: 245/45R17 95W
Spare tire: T125/70D17 98M
Front and rear tire inflation pres-
sure
(Recommended cold tire inflation
pressure)
Driving under normal conditions
Front:
35 psi (240 kPa, 2.4 kgf/cm
2 or bar)*
Rear:
38 psi (260 kPa, 2.6 kgf/cm
2 or bar)*
Spare:
60 psi (420 kPa, 4.2 kgf/cm
2 or bar)
*: When driving at high speeds above 100 mph (160 km/h), in countries where such speeds
are permitted by law, add 4.5 psi (30 kPa, 0.3
kgf/cm
2 or bar) to the front tires and rear
tires. Never exceed the maximum cold tire
inflation pressure indicated on the tire side-
wall.
Wheel size17  8J, 17  4T (spare)
Wheel nut torque76 ft•lbf (103 N•m, 10.5 kgf•m)

573
6-1. Specifications
6
Vehicle specifications
Type B
Ti r e s i z e
Front tires: 225/45R17 91V
Rear tires: 245/45R17 95V
Spare tire: T125/70D17 98M
Front and rear tire inflation pres-
sure
(Recommended cold tire inflation
pressure)
Driving under normal conditionsFront:
35 psi (240 kPa, 2.4 kgf/cm
2 or bar)*
Rear:
38 psi (260 kPa, 2.6 kgf/cm
2 or bar)*
Spare:
60 psi (420 kPa, 4.2 kgf/cm
2 or bar)
*: When driving at high speeds above 100 mph (160 km/h), in countries where such speeds
are permitted by law, add 7.2 psi (50 kPa, 0.5
kgf/cm
2 or bar) to the front tires and rear
tires. Never exceed the maximum cold tire
inflation pressure indicated on the tire side-
wall.
Wheel size17  8J, 17  4T (spare)
Wheel nut torque76 ft•lbf (103 N•m, 10.5 kgf•m)

574
6-1. Specifications
Ty p e C
Ti r e s i z e
Front tires: 225/40R18 88Y
Rear tires: 255/40R18 95Y
Spare tire: T145/70D17 106M
Front and rear tire inflation pres-
sure
(Recommended cold tire inflation
pressure)
Driving under normal conditions Front:
35 psi (240 kPa, 2.4 kgf/cm
2 or bar)*
Rear:
38 psi (260 kPa, 2.6 kgf/cm
2 or bar)*
Spare:
60 psi (420 kPa, 4.2 kgf/cm
2 or bar)
*: When driving at high speeds above 100 mph (160 km/h), in countries where such speeds
are permitted by law, add 7.2 psi (50 kPa, 0.5
kgf/cm
2 or bar) to the front tires and rear
tires. Never exceed the maximum cold tire
inflation pressure indicated on the tire side-
wall.
Wheel size
Front wheels: 18  8J
Rear wheels: 18 8 1 /2J
Spare wheel: 17  4T
Wheel nut torque76 ft•lbf (103 N•m, 10.5 kgf•m)

575
6-1. Specifications
6
Vehicle specifications
Type D
Ti r e s i z e
Front tires: 225/40R18 88W
Rear tires: 255/40R18 95W
Spare tire: T145/70D17 106M
Front and rear tire inflation pres-
sure
(Recommended cold tire inflation
pressure)
Driving under normal conditionsFront:
35 psi (240 kPa, 2.4 kgf/cm
2 or bar)*
Rear:
38 psi (260 kPa, 2.6 kgf/cm
2 or bar)*
Spare:
60 psi (420 kPa, 4.2 kgf/cm
2 or bar)
*: When driving at high speeds above 100 mph (160 km/h), in countries where such speeds
are permitted by law, add 7.2 psi (50 kPa, 0.5
kgf/cm
2 or bar) to the front tires and rear
tires. Never exceed the maximum cold tire
inflation pressure indicated on the tire side-
wall.
Wheel size
Front wheels: 18  8J
Rear wheels: 18 8 1 /2J
Spare wheel: 17  4T
Wheel nut torque76 ft•lbf (103 N•m, 10.5 kgf•m)

576
6-1. Specifications
Ty p e E
Ti r e s i z eFront tires: 225/40RF18 88V
Rear tires: 255/40RF18 95V
Front and rear tire inflation pres-
sure
(Recommended cold tire inflation
pressure)
Driving under normal conditions Front:
35 psi (240 kPa, 2.4 kgf/cm
2 or bar)*
Rear:
38 psi (260 kPa, 2.6 kgf/cm
2 or bar)*
*: When driving at high speeds above 100 mph (160 km/h), in countries where such speeds
are permitted by law, add 11.7 psi (80 kPa,
0.8 kgf/cm
2 or bar) to the front tires and rear
tires. Never exceed the maximum cold tire
inflation pressure indicated on the tire side-
wall.
Wheel sizeFront wheels: 18  8J
Rear wheels: 18 8 1 /2J
Wheel nut torque76 ft•lbf (103 N•m, 10.5 kgf•m)