2008 Lexus GX470 diagnostic

316
4-2. Maintenance
Emission inspection and maintenance (I/M) programs
Some states have vehicle emission inspection programs which include
OBD (On Board Diagnostics) checks. The OBD system monitors the oper-
ation of the emission control system.
■If the malfunction indicator lamp comes on
The OBD system determines that a problem exists somewhere in
the emission control system. Your vehicle may not pass the I/M test
and may need to be repaired. Cont act your Lexus dealer to service
the vehicle.
■ Your vehicle may not pass the I/M test:
●When the battery is disconnected or discharged
Readiness codes that are set du ring ordinary driving are erased.
Also, depending on your driving habits, the readiness codes may
not be completely set.
● When the fuel tank cap is loose
The malfunction indicator lamp comes on as a temporary mal-
function and your vehicle may not pass the I/M test.
■ When the malfunction indicator la mp goes off after several driv-
ing trips
The error code in the OBD system will not be cleared unless the
vehicle is driven 40 or more times.
■ If your vehicle does not pass the I/M test
Contact your Lexus dealer to prepare the vehicle for re-testing.

5
When trouble arises
379
5-1. Essential information
Event data recorder
In a crash or a near car crash eventThe EDR may record some or all of the following information.
● Engine speed
● Whether the brake pedal was applied or not
● Ve h i c l e s p e e d
● To what extent the accelerator pedal was depressed
● Position of the transmission shift lever
● Whether the driver and front passenger wore seat belts or not
● Driver’s seat position
● Front passenger’s occupant classification
● SRS airbag deployment data
● SRS airbag system diagnostic data
Your Lexus’ Electronic Control Unit (ECU) may contain another EDR.
There are a variety of driving situations which include activating the vehi-
cle stability control (VSC) under which the VSC EDR will record certain
information. The VSC EDR may record some or all of the following infor-
mation:
● Behavior of the vehicle
● Steering wheel angle
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 troubleshooting, there is a system to record
data in a crash or a near car crash event. This is called an Event Data
Recorder (EDR).

380
5-1. Essential information
●Ve h i c l e s p e e d
● To what extent the accelerator pedal was depressed
● To what extent the brake pedal was applied
● To what extent the ECU controlled the condition of the 4 wheels
● Vehicle stability control system diagnostic data
The information above is intended to be used for the purpose of improv-
ing vehicle safety performance. Unlike 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 agreement from the vehicle’s owner (or the leasing company for a
leased vehicle) is obtained
● Officially requested by the police or other authorities
● Used as a defense for Lexus in a law suit
● Ordered by a court
However, if necessary Lexus will:
● Use the data for research on Lexus vehicle safety performance
● Disclose the data to a third party for research purposes without dis-
closing details of the vehicle owner, and only when it is deemed neces-
sary
● Disclose summarized data cleared of vehicle identification information
to a non-Lexus organization for research purposes

444
Abbreviation list
Abbreviation/Acronym list
ABBREVIVATIONSMEANING
A/CAir Conditioning
ABSAnti-Lock Brake System
ACCAccessory
ALRAutomatic Locking Retractor
CALCalibration
CRSChild Restraint System
DACDownhill Assist control system
DISPDisplay
ECUElectronic Control Unit
EDREvent data recorder
ELREmergency Locking Retractor
GAWRGross Axle Weight Ratings
I/MEmission inspection and maintenance
INTIntermittent
KDSSKinetic Dynamic Suspension System
LEDLight Emitting Diode
LSDLimited Slip Differential
MMTMethylcy clopentadienyl Manganese Tricarbonyl
M + SMud and Snow
MTBEMethyl Tertiary Butyl Ether
OBDOn Board Diagnostics