ECU Lexus GS450h 2007 Using the audio system / LEXUS 2007 GS450H THROUGH JUNE 2006 PROD. (OM30727U) Service Manual

418
4-3. Do-it-yourself maintenance
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 ente ring the headlight unit. This may damage
the headlights or cause condensation to build up on the lens.
●Do not attempt to repair or disassemble lig ht bulbs, connectors, electric circuits
or component parts. 
Doing so may result in serious injury due to electric shock.
■High-intensity discharge (HID) headlights
●Contact your Lexus dealer before replac ing high-intensity discharge headlights
(including light bulbs).
●Do not touch the high voltage socket while the headlights are turned on.
20000V is momentarily generated and ma y cause severe injury by electric
shock.
■To prevent damage or fire
Make sure bulbs are fully seated and locked.

420
5-1. Essential information
If your vehicle needs to be towed
Before towing
The following may indicate a problem with your transmission. Contact
your Lexus dealer before towing.
● The hybrid s
ystem is running, but the vehicle will not move.
● The v
ehicle 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 ch ain secur
ed to the emergency towing
eyelet. This should only attempted on hard, surfaced roads for short dis-
tances at low speeds. 
A driver must be in the vehicle to steer and oper
ate the brakes. The vehi-
cle’s wheels, drive train, axles, steering and br
akes must be in good condi -
tion.
If towing is necessary, we recommen d having your vehicle towed by your
Lexus dealer or a commercial towing service, using a lift-type truck or a flat
bed truck.

Use a safety chain system for all towing , a
nd abide by all state/provincial
and local laws.
The wheels and axle on the ground must be in good condition.
If they are damaged, use a to wing dolly
or flat bed truck.

422
5-1. Essential information
Installing towing eyelet
Remove 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
secur
ely using a wheel nut wrench.
STEP1
STEP2
STEP3
■Location of the emergency towing eyelet
P.
4 5 6

5
When trouble arises
423
5-1. Essential information
Towing with a sling-type truck
CAUTION
■Installing towing eyelet to the vehicle
Make sure that towing eyelet is installed securely.
If not securely installed, towing eyelet ma y 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.

428
5-1. Essential information
Event data recorder
In a crash or a near car crash event
The EDR may record some or all of the following information.
●Gasoline engine speed
● Whether the br
ake pedal was applied or not
● V
ehicle speed
●T
o what extent the accelerator pedal was depressed
●P
osition of the transmission shift lever
●Whether the driv
er and front passenger wore seat belts or not
● D
river's seat position
●SRS airbag deplo
yment data
● SRS airbag s
ystem diagnostic data
Your Lexus’ Electronic Control Un it (ECU) may contain another EDR.
Ther
e are a variety of driving situation s which include activating the vehi -
cle stability control (VSC) under whic h the V
SC EDR will record certain
information. The VSC EDR may record so me or all of the following infor-
mation:
● Behavior of the v
ehicle
● Steering wheel angle
●Vehicle speed
Your vehicle has computers that monitor and control certain aspects of
your vehicle. These computers assist in driving and maintaining optimal
vehicle performance.
Besides storing data useful for troublesh ooting, there is a system to record
data in a crash or a near car crash event. This is called an Event Data
Recorder (EDR).

5
When trouble arises
429
5-1. Essential information
●To what extent the accelerator pedal was depressed
● T
o what extent the brake pedal was applied
●T
o what extent the ECU controlled the condition of the 4 wheels
● V
ehicle stability control system diagnostic data
The information above is intended to be used for the purpose of impr
ov-
ing vehicle safety performance. Unlik
e general data recorders, the EDR
does not record sound data such as conversation between passengers.
Disclosure of the data
Lexus will not disclose the data recorded in an EDR to a third party
except when:
●An agr
eement from the vehicle's ow ner (or the leasing company for a
leased vehicle) is obtained
● Of
ficially requested by the police or other authorities
●Used as a defense for L
exus in a law suit
● Or
dered by a court
However, if necessary Lexus will:
●Use the data for r
esearch on Lexus vehicle safety performance
● Disclose the data to a thir
d party for research purposes without dis -
closing details of the vehicle owner, and only when it is deemed neces -
sary
● Disclose summariz
ed data cleared of vehicle id entification information
to a non-Lexus organization for research purposes

434
5-2. Steps to take in an emergency
■If the malfunction indicator lamp comes on while driving
First check the following:
●Is your vehicle low on gas?
If it is, refuel the vehicle immediately.
●Is the fuel tank cap loose? 
If it is, tighten it securely.
The light will go off after taking several driving trips. 
If the light does not go off even after several trips, contact your Lexus dealer as soon
a
s possible.
■Front passenger detection sensor and passenger seat belt reminder
●If luggage is placed on the front passenger seat, the front passenger detection
sensor may cause the warning light to flash, 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.
■SRS warning light
This warning light system monitors the following:
●The airbag sensor assembly
●Front airbag sensors
●The curtain shield airbag sensors
●The side and curtain shield airbag sensors
●The occupant detection sensor
●The seat belt buckle switches
●The driver's seat position sensor
●The inflators
●The warning light
●The interconnecting wiring and power sources

458
5-2. Steps to take in an emergency
Taking out the spare tire
Lift up the hook of the panel on the
trunk floor.
Secure the panel using the hook
pr
ovided.
Loosen the center fastener that
secur
es the spare tire.
STEP1
STEP2
STEP3

5
When trouble arises
463
5-2. Steps to take in an emergency
CAUTION
■Using the tire jack
Improper use of the tire jack may lead to death or injuries due to the vehicle sud-
denly 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 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.
●Use a jack stand if it is necessary to get under the vehicle.
●Do not put any part of your body under the vehicle supported by a jack.
●Do not start or run the hybrid system while your vehicle is supported by the jack.
Take particular care when lowering the vehicle to ensure that no one working on or
near the vehicle may be injured.
■Replacing a flat tire
Observe the following precautions to reduce the risk of injury.
●Never use oil or grease on the wheel bolts or wheel nuts. 
The oil or grease can cause the wheel nuts to loosen, causing a serious accident.
Remove any oil or grease on the wheel bolts or wheel nuts.
●Have the wheel nuts tightened with a torque wrench to 76 ft•lbf (103 N•m, 10.5
kgf•m) as soon as possible after changing wheels. 
Failure to follow these precautions could cause the nuts to loosen and the wheels
may fall off, which could lead to an accident causing death or serious injury.