service LEXUS GS400 2000 Service User Guide

EC0BD±02
B02709
Gasket
Vacuum
Valve Pressure
Valve
B06544
Vacuum
Gauge
B01982
LEXUS Hand±Held Tester
DLC 3
B06548Battery
± EMISSION CONTROL (2JZ±GE)EVAPORATIVE EMISSION (EVAP) CONTROL SYSTEM
EC±7
1458 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
INSPECTION
1. INSPECT LINES AND CONNECTORS
Visually check for loose connections, sharp bends or damage.
2. INSPECT FUEL TANK FILLER PIPE
Visually check for deformation, cracks or fuel leakage.
3. VISUALLY INSPECT FUEL TANK CAP
Check if the cap and/or gasket are deformed or damaged.
If necessary, repair or replace the cap.
4. INSPECT EVAP SYSTEM LINE
(a) Warm up the engine and stop the engine.
Allow the engine to warm up to normal operating tempera-
ture.
(b) Install a vacuum gauge (EVAP control system test equip-
ment vacuum gauge) to the EVAP service port on the
purge line.
(c) LEXUS Hand±Held Tester:
Forced driving of the VSV for the EVAP.
(1) Connect a LEXUS hand±held tester to the DLC3.
(2) Start the engine.
(3) Push the LEXUS hand±held tester main switch ON.
(4) Use the ACTIVE TEST mode on the LEXUS hand±
held tester to operate the VSV for the EVAP.
(d) If you have no LEXUS Hand±Held Tester:
Forced driving of the VSV for the EVAP.
(1) Disconnect the VSV connector for the EVAP.
(2) Connect the positive (+) and negative (±) leads from
the battery to the VSV terminals for the EVAP.
(3) Start the engine.

B06545
B06743Hose ClipperAir Drain Hose
B06546
Pressure
Gauge
Pressure EC±8
± EMISSION CONTROL (2JZ±GE)EVAPORATIVE EMISSION (EVAP) CONTROL SYSTEM
1459 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
(e) Check the vacuum at idle.
Vacuum:
Maintain at 0.368 ± 19.713 in.Hg (5 ± 268 in.Aq) for over
5 seconds
HINT:
If the vacuum does not change, you can conclude that the hose
connecting the VSV to the service port has come loose or is
blocked, or the VSV is malfunctioning.
(f) LEXUS Hand±Held Tester:
Conclude forced driving of the VSV for the EVAP.
(1) Stop the engine.
(2) Disconnect the LEXUS hand±held tester from the
DLC3.
(g) If you have no LEXUS Hand±Held Tester:
Conclude forced driving of the VSV for the EVAP.
(1) Stop the engine.
(2) Disconnect the positive (+) and negative (±) leads
from the battery from the VSV terminals for the
EVAP.
(3) Connect the VSV connector for the EVAP.
(h) Disconnect the vacuum gauge from the EVAP service
port on the purge line.
(i) Connect a pressure gauge to the EVAP service port on
the purge line.
(j) Check the pressure.
(1) Close off the air drain hose at the marked position
of the canister with a hose clipper or similar instru-
ment.
(2) Add the pressure (13.5 ± 15.5 in.Aq) from the EVAP
service port.
Pressure:
2 minutes after the pressure is added, the gauge
should be over 7.7 ± 8.8 in.Aq.
HINT:
If you can't add pressure, you can conclude that the hose con-
necting the VSV
canister
fuel tank has slipped off or the
VSV is open.

B06547
Fuel Tank Cap
B06840
AirDisconnect
EVAP Line Hose
B06841Air
Disconnect
Plug
Disconnect
EVAP Line Hose
Purge Line
Hose
Purge Port
± EMISSION CONTROL (2JZ±GE)EVAPORATIVE EMISSION (EVAP) CONTROL SYSTEM
EC±9
1460 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
(3) Check if the pressure decreases when the fuel tank
cap is removed while adding pressure.
HINT:
If the pressure does not decrease when the filler cap is re-
moved, then you can conclude that the hose connecting the
service port to the fuel tank is blocked, etc.
(k) Disconnect the pressure gauge from the EVAP service
port on the purge line.
5. CHECK AIRTIGHTNESS IN FUEL TANK AND FILLER
PIPE
(a) Disconnect the EVAP line hose from the charcoal canister
side and then pressurize and make the internal pressure
in the fuel tank 4 kPa (41 gf/cm
2, 0.58 psi).
(b) Check that the internal pressure of the fuel tank can be
hold for 1 minute.
(c) Check the connected portions of each hose and pipe.
(d) Check the installed parts on the fuel tank.
If there is no abnormality, replace the fuel tank and filler pipe.
(e) Reconnect the EVAP line hose to the charcoal canister.
6. INSPECT FUEL CUTOFF VALVE AND FILL CHECK
VA LV E
(a) Disconnect the purge line hose and EVAP line hose from
the charcoal canister.
(b) Disconnect the air drain hose from the canister tank, and
plug its.
(c) Pressurize 4 kPa (41 gf/cm
2, 0.58 psi) to the purge port
and check that there is ventilation through the EVAP line
hose.
HINT:
In the condition that the fuel fuel is full, as the float value of the
fill check valve is closed and has no ventilation, it is necessary
to check the fuel amount (volume).
(d) Check if there is any struck in the vent line hose and EVAP
line hose.
If there is no stuck in hoses, replace the fuel cutoff valve and fill
check valve.
(e) Reconnect the purge line hose and EVAP line hose to the
charcoal canister.
(f) Reconnect the air drain hose to the canister tank.

IN00U±35
N17080
Filler Cap
Float
Reservoir Tank
 Grommet
Clip
Slotted Spring Pin
: Specified torque
 Non±reusable partCylinder
Piston
Push Rod
Washer
Snap Ring
Boot
 Gasket
Lock Nut
Clevis Pin
Clevis
N´m (kgf´cm, ft´lbf)
12 (120, 9)
15 (155, 11)
± INTRODUCTIONHOW TO USE THIS MANUAL
IN±1
1 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
HOW TO USE THIS MANUAL
GENERAL INFORMATION
1. INDEX
An INDEX is provided on the first page of each section to guide you to the item to be repaired. To assist you
in finding your way through the manual, the section title and major heading are given at the top of every page.
2. PRECAUTION
At the beginning of each section, a PRECAUTION is given that pertains to all repair operations contained
in that section.
Read these precautions before starting any repair task.
3. TROUBLESHOOTING
TROUBLESHOOTING tables are included for each system to help you diagnose the problem and find the
cause. The fundamentals of how to proceed with troubleshooting are described on page IN±21.
Be sure to read this before performing troubleshooting.
4. PREPARATION
Preparation lists the SST (Special Service Tools), recommended tools, equipment, lubricant and SSM (Spe-
cial Service Materials) which should be prepared before beginning the operation and explains the purpose
of each one.
5. REPAIR PROCEDURES
Most repair operations begin with an overview illustration. It identifies the components and shows how the
parts fit together.
Example:

Illustration:
what to do and where
21. CHECK PISTON STROKE OF OVERDRIVE BRAKE
(a)
Task heading : what to do
SST 09350±30020 (09350±06120)
Set part No. Component part No.
Detailed text : how to do task
(b)
Piston stroke: 1.40 1.70 mm (0.0551 0.0669 in.)
Specification
Place SST and a dial indicator onto the overdrive brake pis-
ton as shown in the illustration.
Measure the stroke applying and releasing the compressed
air (392 785 kPa, 4 8 kgf/cm
2 or 57 114 psi) as shown
in the illustration. IN±2
± INTRODUCTIONHOW TO USE THIS MANUAL
2 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
The procedures are presented in a step±by±step format:

The illustration shows what to do and where to do it.

The task heading tells what to do.

The detailed text tells how to perform the task and gives other information such as specifications
and warnings.
Example:
This format provides the experienced technician with a FAST TRACK to the information needed. The upper
case task heading can be read at a glance when necessary, and the text below it provides detailed informa-
tion. Important specifications and warnings always stand out in bold type.
6. REFERENCES
References have been kept to a minimum. However, when they are required you are given the page to refer
to.
7. SPECIFICATIONS
Specifications are presented in bold type throughout the text where needed. You never have to leave the
procedure to look up your specifications. They are also found in Service Specifications section for quick ref-
erence.
8. CAUTIONS, NOTICES, HINTS:

CAUTIONS are presented in bold type, and indicate there is a possibility of injury to you or other
people.

NOTICES are also presented in bold type, and indicate the possibility of damage to the components
being repaired.

HINTS are separated from the text but do not appear in bold. They provide additional information to
help you perform the repair efficiently.
9. SI UNIT
The UNITS given in this manual are primarily expressed according to the SI UNIT (International System of
Unit), and alternately expressed in the metric system and in the English System.
Example:
Torque: 30 N´m (310 kgf´cm, 22 ft´lbf)

IN0EI±01
BO4111
Negative Cable
IN±10
± INTRODUCTIONFOR ALL OF VEHICLES
10 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
FOR ALL OF VEHICLES
PRECAUTION
1. FOR VEHICLES EQUIPPED WITH SRS AIRBAG AND
SEAT BELT PRETENSIONER
(a) The LEXUS GS400/GS300 is equipped with an SRS
(Supplemental Restraint System), such as the driver air-
bag, front passenger airbag assembly, side airbag as-
sembly and seat belt pretensioners.
Failure to carry out service operations in the correct se-
quence could cause the supplemental restraint system to
unexpectedly deploy during servicing, possibly leading to
a serious accident.
Further, if a mistake is made in servicing the supplemental
restraint system, it is possible the SRS may fail to operate
when required. Before servicing (including removal or
installation of parts, inspection or replacement), be sure
to read the following items carefully, then follow the cor-
rect procedure described in this manual.
(b) GENERAL NOTICE
(1) Malfunction symptoms of the supplemental re-
straint system are difficult to confirm, so the diag-
nostic trouble codes become the most important
source of information when troubleshooting. When
troubleshooting the supplemental restraint system,
always inspect the diagnostic trouble codes before
disconnecting the battery (See page DI±552).
(2) Work must be started after 90 seconds from the
time the ignition switch is turned to the ºLOCKº posi-
tion and the negative (±) terminal cable is discon-
nected from the battery.
(The supplemental restraint system is equipped
with a back±up power source so that if work is
started within 90 seconds of disconnecting the neg-
ative (±) terminal cable from the battery, the SRS
may deploy.)
When the negative (±) terminal cable is discon-
nected from the battery, memory of the clock and
audio systems will be cancelled. So before starting
work, make a record of the contents memorized by
the each memory system. Then when work is fin-
ished, reset the clock and audio systems as before.
This vehicle has power tilt and power telescopic
steering, power seat and power outside rear view
mirror, which are all equipped with memory function,
it is not possible to make a record of the memory
contents. So when the work is finished, therefore it
will be necessary to explain this fact to the custom-
er, and ask the customer to adjust the features and

IN04S±10
IN±20± INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMS
20 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS
GENERAL INFORMATION
A large number of ECU controlled systems are used in the LEXUS GS400/GS300. In general, the ECU con-
trolled system is considered to be a very intricate system requiring a high level of technical knowledge and
expert skill to troubleshoot. However, the fact is that if you proceed to inspect the circuits one by one, trouble-
shooting of these systems is not complex. If you have adequate understanding of the system and a basic
knowledge of electricity, accurate diagnosis and necessary repair can be performed to locate and fix the
problem. This manual is designed through emphasis of the above standpoint to help service technicians
perform accurate and effective troubleshooting, and is compiled for the following major ECU controlled sys-
tems:
The troubleshooting procedure and how to make use of it are described on the following pages.
SystemPage
1. Engine 2JZ ± GEDI±1
2. Engine 1UZ ± FEDI±156
3. Automatic TransmissionDI±316
4. ABS & Hydraulic Brake Booster Power Supply SystemDI±387
5. Vehicle Skid Control (VSC) & Brake Assist (BA) SystemDI±473
6. Power Tilt and Power Telescopic Steering ColumnDI±517
7. Supplemental Restraint SystemDI±550
8. Power Seat Control SystemDI±683
9. Cruise Control SystemDI±704
10.Engine Immobiliser SystemDI±726
11. Combination Meter SystemDI±744
12.Sliding Roof SystemDI±764
13.Body No. 1 Control SystemDI±776
14.Body No. 2 Control SystemDI±820
15.Driver Door Control SystemDI±856
16.Passenger Door Control SystemDI±889
17.Rear Left Door Control SystemDI±921
18.Rear Right Door Control SystemDI±938
19.Multiplex Communication SystemDI±955
20.LEXUS Navigation SystemDI±1022
21.Air Conditioning SystemDI±1059
FOR USING OBDII SCAN TOOL OR LEXUS HAND±HELD TESTER

Before using the scan tool or tester, the scan tool's instruction book or tester's operator manual should
be read thoroughly.

If the scan tool or tester cannot communicate with ECU controlled systems when you have connected
the cable of the scan tool or tester to DLC3, turned the ignition switch ON and operated the scan tool,
there is a problem on the vehicle side or tool side.
(1) If communication is normal when the tool is connected to another vehicle, inspect the diagnosis
data link line (Bus
line) or ECU power circuit of the vehicle.
(2) If communication is still not possible when the tool is connected to another vehicle, the problem
is probably in the tool itself, so perform the Self Test procedures outline in the Tester Operator's
Manual.

± INTRODUCTIONTERMS
IN±39
39 Author: Date:
2000 LEXUS GS300/GS400 (RM718U) OEM
Original Equipment Manufacturing
OHCOverhead Camshaft
OHVOverhead Valve
OPTOption
O/SOversize
P & BVProportioning And Bypass Valve
PCSPower Control System
PCVPositive Crankcase Ventilation
PKBParking Brake
PPSProgressive Power Steering
PSPower Steering
PTOPower Take±Off
R & PRack And Pinion
R/BRelay Block
RBSRecirculating Ball Type Steering
R/FReinforcement
RFSRigid Front Suspension
RHRight±Hand
RHDRight±Hand Drive
RLYRelay
ROMRead Only Memory
RrRear
RRRear±Engine Rear±Wheel Drive
RRSRigid Rear Suspension
RWDRear±Wheel Drive
SDNSedan
SENSensor
SICSStarting Injection Control System
SOCState Of Charge
SOHCSingle Overhead Camshaft
SPECSpecification
SPISingle Point Injection
SRSSupplemental Restraint System
SSMSpecial Service Materials
SSTSpecial Service Tools
STDStandard
STJCold±Start Fuel Injection
SWSwitch
SYSSystem
T/ATransaxle
TACHTachometer
TBIThrottle Body Electronic Fuel Injection
TCTurbocharger
TCCSTOYOTA Computer±Controlled System
TCVTiming Control Valve
TDCTop Dead Center

BE1367
Medium Current Fuse and High Current Fuse
Equal Amperage Rating
V00076
Abbreviation Part Name Symbol Illustration
FUSE
MEDIUM CURRENT FUSE
HIGH CURRENT FUSE
FUSIBLE LINK
CIRCUIT BREAKERFUSE
M±FUSE
H±FUSE
FL
CB
± INTRODUCTIONREPAIR INSTRUCTIONS
IN±5
5 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
(3) Precoated parts are indicated in the component il-
lustrations by the º
º symbol.
(g) When necessary, use a sealer on gaskets to prevent
leaks.
(h) Carefully observe all specifications for bolt tightening
torques. Always use a torque wrench.
(i) Use of special service tools (SST) and special service ma-
terials (SSM) may be required, depending on the nature
of the repair. Be sure to use SST and SSM where speci-
fied and follow the proper work procedure. A list of SST
and SSM can be found in Preparation section in this
manual.
(j) When replacing fuses, be sure the new fuse has the cor-
rect amperage rating. DO NOT exceed the rating or use
one with a lower rating.

IN±42
± INTRODUCTIONTERMS
42 Author: Date:
2000 LEXUS GS300/GS400 (RM718U) HO2S
Heated Oxygen SensorHeated Oxygen Sensor (HO2S)
IACIdle Air ControlIdle Speed Control (ISC)
IATIntake Air TemperatureIntake or Inlet Air Temperature
ICMIgnition Control Module±
IFIIndirect Fuel InjectionIndirect Injection (IDL)
IFSInertia Fuel±Shutoff±
ISCIdle Speed Control±
KSKnock SensorKnock Sensor
MAFMass Air FlowAir Flow Meter
MAPManifold Absolute PressureManifold Pressure
Intake Vacuum
MCMixture Control
Electric Bleed Air Control Valve (EBCV)
Mixture Control Valve (MCV)
Electric Air Control Valve (EACV)
MDPManifold Differential Pressure±
MFIMultiport Fuel InjectionElectronic Fuel Injection (EFI)
MILMalfunction Indicator LampCheck Engine Lamp
MSTManifold Surface Temperature±
MVZManifold Vacuum Zone±
NVRAMNon±Volatile Random Access Memory±
O2SOxygen SensorOxygen Sensor, O2 Sensor (O2S)
OBDOn±Board DiagnosticOn±Board Diagnostic System (OBD)
OCOxidation Catalytic ConverterOxidation Catalyst Convert (OC), CCo
OPOpen LoopOpen Loop
PAIRPulsed Secondary Air InjectionAir Suction (AS)
PCMPowertrain Control Module±
PNPPark/Neutral Position±
PROMProgrammable Read Only Memory±
PSPPower Steering Pressure±
PTOXPeriodic Trap OxidizerDiesel Particulate Filter (DPF)
Diesel Particulate Trap (DPT)
RAMRandom Access MemoryRandom Access Memory (RAM)
RMRelay Module±
ROMRead Only MemoryRead Only Memory (ROM)
RPMEngine SpeedEngine Speed
SCSuperchargerSupercharger
SCBSupercharger BypassE±ABV
SFISequential Multiport Fuel InjectionElectronic Fuel Injection (EFI), Sequential Injection
SPLSmoke Puff Limiter±
SRIService Reminder Indicator±
SRTSystem Readiness Test±
STScan Tool±
TBThrottle BodyThrottle Body
TBIThrottle Body Fuel InjectionSingle Point Injection
Central Fuel Injection (Ci)
TCTurbochargerTurbocharger
TCCTorque Converter ClutchTorque Converter