2012 Lexus IS250 ECU

445
4-3. Do-it-yourself maintenance
4
Maintenance and care
IS350/250_U
14RR DOOR LH20 APo w e r w i n d o w s
15FR DOOR LH20 APower windows, outside rear view
mirror
16SECURITY7. 5 ASmart access system with push-button
start
17H-LP LVL7. 5 AAutomatic headlight leveling system
18LH-IG10 A
Charging system, headlight cleaner,
rear window defogger, electric cool-
ing fans, emergency flashers, turn sig-
nal lights, back-up lights, stop lights,
mirror heaters, rear sun shade, seat
belts, intuitive parking assist, cruise
control, air conditioning system, PTC
heater, manual transmission, wind-
shield wiper de-icer
19FR WIP30 AWindshield wipers
FuseAmpereCircuit

447
4-3. Do-it-yourself maintenance
4
Maintenance and care
IS350/250_U
9ACC7. 5 A
Clock, air conditioning system, audio,
navigation system, outside rear view
mirrors, Lexus parking assist monitor,
glove box light, console box light, mul-
tiplex communication system, display,
smart access system with push-but-
ton start
10CIG15 ACigarette lighter
11PWR OUTLET15 APo w e r o u t l e t
12RR DOOR RH20 APo w e r w i n d o w s
13FR DOOR RH20 A
Po w e r w i n d o w s , o u t s i d e r e a r v i e w
mirrors, multiplex communication sys-
tem
14AM27. 5 AStarting system
15RH-IG7. 5 A
Seat belts, intuitive parking assist,
automatic transmission, seat heater
and ventilator, windshield wiper de-
icer
16FR S/HTR RH15 ASeat heaters and ventilators
17ECU-IG RH10 A
Power seats, smart access system with
push-button start, AWD system, out-
side rear view mirrors, VDIM, air con-
ditioning system, electric tilt and
telescopic steering, power windows,
navigation system, multiplex commu-
nication system
FuseAmpereCircuit

458
4-3. Do-it-yourself maintenance
IS350/250_U
■When replacing the front left headlight and parking light (vehicles with halogen
headlights) bulbs
■Condensation build-up on the inside of the lens
Contact your Lexus dealer for more information in the following situations. Tempo-
rary condensation build-up on the inside of the headlight lens does not indicate a
malfunction.
●Large drops of water are built up on the inside of the lens.
●Water has built up inside the headlight.
■Discharge headlights (if equipped)
If voltage to the discharge bulbs is insufficient, the bulbs may not come on, or may
go out temporarily. The discharge bulbs will come on when normal power is
restored.
■LED front side marker lights, side turn signal lights, tail lights, stop/tail lights, high
mounted stoplight, rear side marker lights, license plate lights and parking lights
(vehicles with discharge headlights)
The front side marker lights, side turn signal lights, tail lights, stop/tail lights, high
mounted stoplight, rear side marker lights, license plate lights and parking lights
(vehicles with discharge headlights) consist of a number of LEDs. If any of the LEDs
burn out, take your vehicle to your Lexus dealer to have the light replaced.Remove the securing bolt and move the
washer fluid filler opening to allow easy
access to the light bulbs.
After replacing the bulbs, make sure to
secure the washer fluid filler opening with the
bolt.

459
4-3. Do-it-yourself maintenance
4
Maintenance and care
IS350/250_U
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 bare 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 entering 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 before 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 will be discharged and could result in
serious injury or death by electric shock.
●Do not attempt to take apart or repair the low beam headlight 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
IS350/250_U
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 steer 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 towing, 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 towing dolly or flat bed truck.

5
When trouble arises
465
5-1. Essential information
IS350/250_U
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
IS350/250_U
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
IS350/250_U
■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 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.
■The tire pressure warning light ma y 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
The compact spare tire is not equipped with 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.