ECU Lexus IS250 2012 Using the Bluetooth audio system / LEXUS 2012 IS250,IS350 (OM53A87U) Workshop Manual

459
4-3. Do-it-yourself maintenance
4
Maintenance and care
CAUTION
■Replacing light bulbs
●Turn off the headlights. Do not attempt to replace the bulb immediately after turn-
ing off the headlights.
The bulbs become very hot and may cause burns.
●Do not touch the glass portion of the light bulb with ba re hands. Hold the bulb by
the plastic or metal portion.
If the bulb is scratched or dropped it may blow out or crack.
●Fully install light bulbs and any parts used to secure them. Failing to do so may
result in heat damage, fire, or water en tering the headlight unit. This may damage
the headlights or cause condensation to build up on the lens.
■Discharge headlights (if equipped)
●Contact your Lexus dealer be fore replacing discharge headlights (including light
bulbs).
●Do not touch the high-intensity discharge headlight’s high voltage socket when
the headlights are turned on.
An extremely high voltage of 20000 V wi ll be discharged and could result in
serious injury or death by electric shock.
●Do not attempt to take apart or repair the low beam headligh t bulbs, connectors,
power supply circuits, or related components.
Doing so could result in electric shock and serious injury or death.
■To prevent damage or fire
Make sure bulbs are fully seated and locked.

5
When trouble arises
463
5-1. Essential information
If your vehicle needs to be towed
Before towingThe following may indicate a problem with your transmission. Contact
your Lexus dealer before towing.
● The engine is running, but the vehicle will not move.
● The vehicle makes an abnormal sound.
Emergency towing
If a tow truck is not available, in an emergency your vehicle may be tem-
porarily towed using a cable or chain secured to the emergency towing
eyelet(s). This should only be attempted on hard, surfaced roads for short
distances at low speeds.
A driver must be in the vehicle to s teer and operate the brakes. The vehi-
cle’s wheels, drive train, axles, steering and brakes must be in good condi-
tion.
Towing eyelets
If towing is necessary, we recommend having your vehicle towed by your
Lexus dealer or a commercial towing se rvice, using a lift-type truck or a flat
bed truck.
Use a safety chain system for all towi ng, and abide by all state/provincial
and local laws.
If towing from the rear, the vehicle’s front wheels and axles must be in good
condition. ( P. 4 6 7 )
If they are damaged, use a to wing dolly or flat bed truck.

5
When trouble arises
465
5-1. Essential information
Installing towing eyeletsRemove the eyelet cover using a
flathead screwdriver.
To protect the bodywork, place a
rag between the screwdriver and
the vehicle body, as shown in the
illustration.
Insert the towing eyelet into the
hole and tighten partially by hand.
Tighten down the towing eyelet
securely using a wheel nut wrench.
STEP1
STEP2
STEP3
■Location of the emergency towing eyelet
P. 4 9 2

466
5-1. Essential information
Towing with a sling-type truck
CAUTION
■Installing towing eyelets to the vehicle
Make sure that towing eyelets are installed securely.
If not securely installed, towing eyelets may come loose during towing. This may
lead to accidents that cause serious injury or even death.
NOTICE
■To prevent body damage
Do not tow with a sling type truck, either from the front or rear.

476
5-2. Steps to take in an emergency
■If the malfunction indicator lamp comes on while driving
First check the following:
●Is the fuel tank 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 warning light
When the battery is low or when the voltage drops temporarily, the electric power
steering warning light may come on.
■Front passenger detection sensor and pass enger 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.
■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 caus ed 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
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.

5
When trouble arises
493
5-2. Steps to take in an emergency
Taking out the spare tireLift up the hook of the panel on the
trunk floor.
Secure the panel using the hook
provided.
Loosen the center fastener that
secures the spare tire.
STEP1
STEP2
STEP3

5
When trouble arises
497
5-2. Steps to take in an emergency
■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 indicated. 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 1 4 )
CAUTION
■Using the tire jack
Improper use of the tire jack may lead to death or serious injuries due to the vehicle
suddenly falling off the jack.
●Do not use the tire jack for any purpose other than replacing tires or installing and
removing tire chains.
●Only use the tire jack that comes with this vehicle for replacing a flat tire.
Do not use it on other vehicles, and do no t use other tire jacks for replacing tires
on this vehicle.
●Always check that the tire jack is securely set to the jack point.
●Do not put any part of your body under the vehicle while it is supported by a jack.
●Do not start or run the engine while your vehicle is supported by the jack.
●Do not raise the vehicle while someone is in it.
●When raising the vehicle, do not put an object on or under the jack.
●Do not raise the vehicle to a height greate r than that required to replace the tire.
STEP1
STEP2
STEP3

506
5-2. Steps to take in an emergency
After the operation is completed,
reinstall the cover.
Hook the upper claw of the cover
onto the upper catch on the vehi-
cle side, and then push on the
lower side of the cover.
Make sure that the lower claw of
the cover is securely fastened to
the lower catch on the vehicle side.
If the cover is not securely
attached, it may fall off while driv-
ing.
Tr u n k
Turn the mechanical key clock-
wise to open.
STEP3

518
5-2. Steps to take in an emergency
If your vehicle has to be stopped in an emergency
CAUTION
■If the engine has to be turned off while driving
Power assist for the brakes and steering wheel will be lost, making the brake pedal
harder to depress and the steering wheel heavier to turn. Decelerate as much as
possible before turning off the engine.
Only in an emergency, such as if it becomes impossible to stop the vehicle
in the normal way, stop the vehicle using the following procedure:
Steadily step on the brake pe dal with both feet and firmly
depress it.
Do not pump the brake pedal repeatedly as this will increase the
effort required to slow the vehicle.
Shift the shift lever to N.
If the shift lever is shifted to N After slowing down, stop the vehicl e in a safe place by the road.
Stop the engine.
If the shift lever cannot be shifted to N Keep depressing the brake pedal with both feet to reduce vehi-
cle speed as much as possible.
Stop the engine by pressing and
holding the “ENGINE START
STOP” switch for 3 consecutive
seconds or more.
Stop the vehicle in a safe place by the road.
STEP1
STEP2
STEP3
STEP4
STEP3
Press and hold for 3 seconds or more
STEP4
STEP5

552
6-1. Specifications
*: Table 1  Occupant loading and distribution for vehicle normal load for
various designated seating capacities
Tr e a d r i bA tread section running circumferentially around a
tire
Tr e a d s e p a r a t i o nPulling away of the tread from the tire carcass
Treadwear indicators
(TWI)The projections within the principal grooves
designed to give a visual indication of the degrees of
wear of the tread
Wheel-holding fixtureThe fixture used to hold the wheel and tire assembly
securely during testing
Designated seating
capacity, Number of occupantsVehicle normal load,
Number of occupantsOccupant distribution in
a normally loaded vehicle
2 through 422 in front
5 through 1032 in front, 1 in second seat
11 through 155
2 in front, 1 in second
seat, 1 in third seat, 1 in fourth seat
16 through 207
2 in front, 2 in second
seat, 2 in third seat, 1 in
fourth seat
Tire related termMeaning