IN0253
WRONG CORRECT
IN0252
WRONG CORRECT IN±6
± INTRODUCTIONREPAIR INSTRUCTIONS
6 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
(k) Care must be taken when jacking up and supporting the
vehicle. Be sure to lift and support the vehicle at the prop-
er locations (See page IN±8).
Cancel the parking brake on the level place and
shift the transmission in Neutral (or N position).
When jacking up the front wheels of the vehicle, at
first place stoppers behind the rear wheels.
When jacking up the rear wheels of the vehicle, at
fitst place stoppers before the front wheels.
When either the front or rear wheels only should be
jacked up, set rigid racks and place stoppers in front
and behind the other wheels on the ground.
After the vehicle is jacked up, be sure to support it
on rigid racks. It is extremely dangerous to do any
work on a vehicle raised on a jack alone, even for
a small job that can be finished quickly.
(l) Observe the following precautions to avoid damage to the
following parts:
(1) Do not open the cover or case of the ECU unless
absolutely necessary. (If the IC terminals are
touched, the IC may be destroyed by static electric-
ity.)
(2) To disconnect vacuum hoses, pull off the end, not
the middle of the hose.
(3) To pull apart electrical connectors, pull on the con-
nector itself, not the wires.
(4) Be careful not to drop electrical components, such
as sensors or relays. If they are dropped on a hard
floor, they should be replaced and not reused.
(5) When steam cleaning an engine, protect the elec-
tronic components, air filter and emission±related
components from water.
(6) Never use an impact wrench to remove or install
temperature switches or temperature sensors.
(7) When checking continuity at the wire connector, in-
sert the tester probe carefully to prevent terminals
from bending.
(8) When using a vacuum gauge, never force the hose
onto a connector that is too large. Use a step±down
adapter for adjustment. Once the hose has been
stretched, it may leak air.
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
PP0O2±02
± PREPARATIONBODY ELECTRICAL
PP±93
145 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
EQUIPMENT
Voltmeter
Ammeter
Ohmmeter
Test lead
ThermometerEngine coolant temperature sender gauge, Engine oil level warn-
ing switch, Seat heater
SyphonBrake fluid level warning switch
Oil bathEngine oil level warning switch
Bulb (1.4 W)Defogger switch
Bulb (3.4 W)Fuel sender gauge, Engine coolant temperature receiver gauge,
Seat belt warning relay
Dry cell batteryFuel sender gauge, Power mirror
Heat lightSeat heater
Hexagon wrench (6 mm)Power seat
Torque wrench
Clip removerFor removing cowl louver
Masking tapeRear window defogger wire
Tin foilRear window defogger wire
SS0CN±02
SS±60
± SERVICE SPECIFICATIONSBODY ELECTRICAL
216 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
BODY ELECTRICAL
SERVICE DATA
DAYTIME RUNNING LIGHT RELAY (MAIN) (Wire Harness Side)
1 ± Ground (Ignition switch position LOCK or ACC)No voltage
1 ± Ground (Ignition switch position ON or START)Battery positive voltage
5 ± Ground (Engine Stop)No voltage
5 ± Ground (Engine Running)Battery positive voltage
7 ± Ground (Constant)Battery positive voltage
9 ± Ground (Constant)Battery positive voltage
AUTOMATIC LIGHT CONTROL SENSOR
(Connector disconnected)
4 ± Ground (Ignition switch position LOCK or ACC)No voltage
4 ± Ground (Ignition switch position ON)5.2 ± 9.0 V
(Connector connected)
1 ± Ground (Ignition switch position LOCK or ACC)No voltage
1 ± Ground (Ignition switch position ON)9.5 V or more
HEADLIGHT BEAM LEVEL CONTROL ECU
(Connector disconnected)
A1 ± A5 (Ignition switch position OFF)26 ± 30 W
A1 ± A6 (Ignition switch position OFF)26 ± 30 W
A1 ± A7 (Ignition switch position OFF)26 ± 30 W
A1 ± A8 (Ignition switch position OFF)26 ± 30 W
A4 ± B4 (Ignition switch position ON and light control switch HEAD)Below 1.5 V
B1 ± B3 (Ignition switch position OFF)3.5 k ± 6.5 kW
B5 ± B7 (Ignition switch position OFF)3.5 k ± 6.5 kW
(Connector disconnected)
B2 ± B3 (Ignition switch position ON)Approx. 2.5 V
B6 ± B7 (Ignition switch position ON)Approx. 2.5 V
B1 ± B3 (Ignition switch position ON)5V
B5 ± B7 (Ignition switch position ON)5V
TURN SIGNAL FLASHER
1 ± Ground (Ignition switch position LOCK or ACC)No voltage
1 ± Ground (Ignition switch position ON)Battery positive voltage
4 ± Ground (Constant)Battery positive voltage
LIGHT FAILURE RELAY (Wire Harness Side)
5 ± Ground (Light control switch position OFF)No voltage
5 ± Ground (Light control switch position TAIL or HEAD)Battery positive voltage
8 ± Ground (Ignition switch position LOCK or ACC)No voltage
8 ± Ground (Ignition switch position ON)Battery positive voltage
9 ± Ground (Stop light switch position OFF)No voltage
9 ± Ground (Stop light switch position ON)Battery positive voltage
10 ± Ground (Stop light switch position OFF)No voltage
10 ± Ground (Stop light switch position ON)Battery positive voltage
SPEEDOMETER (ON±VEHICLE)
USA:
B01374
EFI Main
Relay
SF0NY±01
A00968
Ohmmeter
No Continuity5 Ohmmeter
Continuity
32
1
A00969
5 Ohmmeter
Continuity32 1
Battery SF±50
± SFI (2JZ±GE)EFI MAIN RELAY
1516 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
EFI MAIN RELAY
INSPECTION
1. REMOVE RELAY BOX COVER
2. REMOVE EFI MAIN RELAY (Marking:EFI)
3. INSPECT EFI MAIN RELAY
(a) Inspect the relay continuity.
(1) Using an ohmmeter, check that there is continuity
between terminals 1 and 2.
If there is no continuity, replace the relay.
(2) Check that there is no continuity between terminals
3 and 5.
If there is continuity, replace the relay.
(b) Inspect the relay operation.
(1) Apply battery positive voltage across terminals 1
and 2.
(2) Using an ohmmeter, check that there is continuity
between terminals 3 and 5.
If there is no continuity, replace the relay.
4. REINSTALL EFI MAIN RELAY
5. REINSTALL RELAY BOX COVER
B01982
LEXUS
Hand±Held
TesterSF0N2±05
B09511
Up
Screw
Pulsation Damper
B01958
Fuel Inlet Hose
A02818
SST
SST
(Union)
SST
(Adapter)
SF±6
± SFI (2JZ±GE)FUEL PUMP
1472 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
FUEL PUMP
ON±VEHICLE INSPECTION
1. CHECK FUEL PUMP OPERATION
(a) Connect a LEXUS hand±held tester to the DLC3.
(b) Turn the ignition switch ON and LEXUS hand±held tester
main switch ON.
NOTICE:
Do not start the engine.
(c) Select the ACTIVE TEST mode on the LEXUS hand±held
tester.
(d) Please refer to the LEXUS hand±held tester operator's
manual for further details.
(e) If you have no LEXUS hand±held tester, connect the pos-
itive (+) and negative (±) leads from the battery to the fuel
pump connector. (See step 3)
(f) Check that the pulsation damper screw rises up when the
fuel pump operates.
If there is no pressure, check the fusible link, fuses, EFI main
relay, fuel pump ECU, fuel pump, ECM and wiring connections.
(g) Turn the ignition switch OFF.
(h) Disconnect the LEXUS hand±held tester from the DLC3.
2. CHECK FUEL PRESSURE
(a) Check the battery positive voltage is above 12 V.
(b) Disconnect the negative (±) terminal cable from the bat-
tery.
(c) Remove the union bolt and 2 gaskets, and disconnect the
fuel inlet hose from the fuel pipe support.
NOTICE:
Put a shop towel under the fuel pipe support.
Slowly loosen the union bolt.
(d) Install the fuel inlet hose and SST (pressure gauge) to the
fuel pipe support with the 3 gaskets and SST (union and
adapter).
SST 09268±45014 (09268±41190, 90405±06167)
Torque: 29 N´m (300 kgf´cm, 21 ft´lbf)
(e) Wipe off any splattered gasoline.
B00923
Starter
RelayST056±01
P07170
OhmmeterContinuity
No Continuity1
3
25
Ohmmeter
P07171
Ohmmeter
Continuity1
3
25
Battery
± STARTING (2JZ±GE)STARTER RELAY
ST±17
1635 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
STARTER RELAY
INSPECTION
1. REMOVE RELAY BOX COVER
2. REMOVE STARTER RELAY
3. INSPECT STARTER RELAY
(a) Inspect the relay continuity.
(1) Using an ohmmeter, check that there is continuity
between terminals 1 and 2.
If there is no continuity, replace the relay.
(2) Check that there is no continuity between terminals
3 and 5.
If there is continuity, replace the relay.
(b) Inspect the relay operation.
(1) Apply battery positive voltage across terminals 1
and 2.
(2) Using an ohmmeter, check that there is continuity
between terminals 3 and 5.
If there is no continuity, replace the relay.
4. REINSTALL STARTER RELAY
5. REINSTALL RELAY BOX COVER