check engine LEXUS GS400 2000 Service Owners Manual

DTC No.
Indicates the diagnostic trouble code.

Page or Instructions
Indicates the page where the inspection procedure
for each circuit is to be found, or gives instructions
for checking and repairs.

Detection Item
Indicates the system of the problem or
contents of the problem.
Trouble Area
Indicates the suspect area of the
problem.
Mass Air Flow Circuit MalfunctionDetection Item

Open or short in mass air flow meter circuit

Mass air flow meter

ECM DTC No.
(See page)Trouble AreaMIL* MemoryP0100
(DI±24)
P0101
(DI±28)
P0115
(DI±33)
Open or short in intake air temp. sensor
circuit

Intake air temp. sensor

ECM Intake Air Temp. Circuit
Malfunction P0110
(DI±29)

Open or short in engine coolant temp. sensor circuit

Engine coolant temp. sensor

ECM
Throttle/ Pedal Position Sensor/Switch
ºAº Circuit MalfunctionEngine Coolant Temp.
Circuit Malfunction

Open or short in throttle position sensor circuit

Throttle position sensor

ECM
DTC CHART (SAE Controlled)
HINT:
Parameters listed in the chart may not be exactly the same as your reading due to the type of instrument or other
factors.
If a malfunction code is displayed during the DTC check mode, check the circuit for that code listed in the table
below. For details of each code, turn to the page referred to under the ºSee pageº for the respective ºDTC No.º
in the DTC chart.
Mass Air Flow Circuit
Range/ Performance Problem
Mass air flow meter

Throttle position sensor Throttle/ Pedal Position Sensor/ Switch
ºAº Circuit Range / Performance Prob-
lem P0116
(DI±37)Engine Coolant Temp.
Circuit Range/ Performance Problem
Engine coolant temp. sensor

Cooling system
± INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMSIN±27
27 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
4. DIAGNOSTIC TROUBLE CODE CHART
The inspection procedure is shown in the table below. This table permits efficient and accurate troubleshoot-
ing using the diagnostic trouble codes displayed in the diagnostic trouble code check. Proceed with trouble-
shooting in accordance with the inspection procedure given in the diagnostic chart corresponding to the
diagnostic trouble codes displayed. The engine diagnostic trouble code chart is shown below as an example.

IN±28± INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMS
28 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
5. PROBLEM SYMPTOMS TABLE
The suspected circuits or parts for each problem symptom are shown in the table below. Use this table to
troubleshoot the problem when a ºNormalº code is displayed in the diagnostic trouble code check but the
problem is still occurring. Numbers in the table indicate the inspection order in which the circuits or parts
should be checked.
HINT:
When the problem is not detected by the diagnostic system even though the problem symptom is present,
it is considered that the problem is occurring outside the detection range of the diagnostic system, or that
the problem is occurring in a system other than the diagnostic system.
Symptom
Suspect AreaSee page
Engine does not crank (Does not start)
No initial combustion (Does not start)
No complete combustion (Does not start)1. Starter and starter relay
1. ECM power source circuit
2. Fuel pump control circuit
3. Engine control module (ECM)
1. Starter signal circuit
2. Fuel pump control circuit1. Fuel pump control circuitDI±147
DI±151
IN±29
PROBLEM SYMPTOMS TABLE
1. Compression
2. Fuel pump control circuit 1. A/C signal circuit
2. Fuel pump control circuit 1. A/C signal circuit (Compressor circuit)
2. ECM power source circuit 1. Starter signal circuit
2. Fuel pump control circuit1. Starter signal circuit
2. Fuel pump control circuit
3. Compression
idling) High engine idle speed (Poor idling) Hot engine Cold engine (Difficult to start)Engine cranks normally (Difficult to start)
AC±88 DI±144
DI±151
EM±3 DI±151

Problem Symptom
Page
Indicates the page where the flow chart for each circuit
is located.

Circuit Inspection, Inspection Order
Indicates the circuit which needs to be checked for each problem
symptom. Check in the order indicated by the numbers.

Circuit or Part Name
Indicates the circuit or part which needs to be checked.
ST±2
ST±17
DI±144
DI±151
DI±144
DI±151

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.

IN0002
Example
± INTRODUCTIONREPAIR INSTRUCTIONS
IN±7
7 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
(m) Installation and removal of vacuum hose:
(1) When disconnecting vacuum hoses, use tags to
identify where they should be reconnected to.
(2) After completing a job, double check that the vacu-
um hoses are properly connected. A label under the
hood shows the proper layout.
(n) Bleeding of hydraulic brake booster:
When repairing the hydraulic brake booster or ABS,
TRAC and VSC system, bleeding the air out of the hy-
draulic brake booster (See page BR±4).
(o) Unless otherwise stated, all resistance is measured at an
ambient temperature of 20°C (68°F). Because the resis-
tance may be outside specifications if measured at high
temperatures immediately after the vehicle has been run-
ning, measurement should be made when the engine has
cooled down.

IN0D6±01
± INTRODUCTIONTERMS
IN±41
41 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
GLOSSARY OF SAE AND LEXUS TERMS
This glossary lists all SAE±J1930 terms and abbreviations used in this manual in compliance with SAE rec-
ommendations, as well as their LEXUS equivalents.
SAE
ABBREVIATIONSSAE TERMSLEXUS TERMS
( )±±ABBREVIATIONS
A/CAir ConditioningAir Conditioner
ACLAir CleanerAir Cleaner, A/CL
AIRSecondary Air InjectionAir Injection (AI)
APAccelerator Pedal±
B+Battery Positive Voltage+B, Battery Voltage
BAROBarometric PressureHAC
CACCharge Air CoolerIntercooler
CARBCarburetorCarburetor
CFIContinuous Fuel Injection±
CKPCrankshaft PositionCrank Angle
CLClosed LoopClosed Loop
CMPCamshaft PositionCam Angle
CPPClutch Pedal Position±
CTOXContinuous Trap Oxidizer±
CTPClosed Throttle PositionLL ON, Idle ON
DFIDirect Fuel Injection (Diesel)Direct Injection (DI)
DIDistributor Ignition±
DLC1
DLC2
DLC3Data Link Connector 1
Data Link Connector 2
Data Link Connector 31: Check Connector
2: Total Diagnosis Comunication Link (TDCL)
3: OBD II Diagnostic Connector
DTCDiagnostic Trouble CodeDiagnostic Code
DTMDiagnostic Test Mode±
ECLEngine Control Level±
ECMEngine Control ModuleEngine ECU (Electronic Control Unit)
ECTEngine Coolant TemperatureCoolant Temperature, Water Temperature (THW)
EEPROMElectrically Erasable Programmable Read Only Memory
Electrically Erasable Programmable Read Only Memory
(EEPROM),
Erasable Programmable Read Only Memory (EPROM)
EFEEarly Fuel EvaporationCold Mixture Heater (CMH), Heat Control Valve (HCV)
EGRExhaust Gas RecirculationExhaust Gas Recirculation (EGR)
EIElectronic IgnitionTOYOTA Distributorless Ignition (TDI)
EMEngine ModificationEngine Modification (EM)
EPROMErasable Programmable Read Only MemoryProgrammable Read Only Memory (PROM)
EVAPEvaporative EmissionEvaporative Emission Control (EVAP)
FCFan Control±
FEEPROMFlash Electrically Erasable Programmable Read Only
Memory±
FEPROMFlash Erasable Programmable Read Only Memory±
FFFlexible Fuel±
FPFuel PumpFuel Pump
GENGeneratorAlternator
GNDGroundGround (GND)

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

B00319
Recommended Viscosity (SAE):
TEMPERATURE RANGE ANTICIPATED BEFORE NEXT OIL CHANGE °F
°C±20
±29 0
±1820
±740
460
1680
27100
38 10W±30
5W±30 PREFERRED
LU05G±04
B01610
Oil PressureOil Pressure SwitchGauge
Union Bolt
P12478
Adhesive
± LUBRICATION (2JZ±GE)OIL AND FILTER
LU±1
1573 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
OIL AND FILTER
INSPECTION
1. CHECK OIL QUALITY
Check the oil for deterioration, entry of water, discoloring or thin-
ning.
If oil quality is visibly poor, replace the oil.
Oil grade:
API grade SJ, Energy±Conserving or ILSAC multi-
grade engine oil. SAE 5W±30 is the best choice for
your vehicle, for good fuel economy, and good start-
ing in cold weather.
2. CHECK ENGINE OIL LEVEL
After warming up the engine and then 5 minutes after the en-
gine stop, oil level should be between the low level and full level
marks of the dipstick.
If low, check for leakage and add oil up to the full level mark.
NOTICE:
Do not fill with engine oil above the full level mark.
3. REMOVE OIL PRESSURE SWITCH, AND INSTALL OIL
PRESSURE GAUGE
(a) Disconnect the oil pressure switch connector.
(b) Using SST, remove the oil pressure switch.
SST 09816±30010
(c) Install an oil pressure gauge.
4. WARM UP ENGINE
Allow the engine to warm up to normal operating temperature.
5. CHECK OIL PRESSURE
Oil pressure:
At idle49 kPa (0.5 kgf/cm2, 7 psi) or more
At 3,000 rpm324 kPa (3.3 kgf/cm2, 47 psi) or more
6. REMOVE OIL PRESSURE GAUGE AND REINSTALL
OIL PRESSURE SWITCH
(a) Remove the oil pressure gauge.
(b) Tighten the union bolt.
Torque: 90 N´m (900 kgf´cm, 66 ft´lbf)
(c) Apply adhesive to 2 or 3 threads of the oil pressure switch.
Adhesive:
Part No.08833±00080, THREE BOND 1344,
LOCTITE 242 or equivalent
(d) Using SST, install the oil pressure switch.
SST 09816±30010
Torque: 15 N´m (150 kgf´cm, 11 ft´lbf)
(e) Connect the oil pressure switch connector.
7. START ENGINE AND CHECK FOR LEAKS

± LUBRICATION (2JZ±GE)OIL AND FILTER
LU±3
1575 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
(b) Fill with fresh engine oil.
Capacity:
Drain and refill w/ Oil filter change
w/o Oil filter change5.4 liters (5.7 US qts, 4.8 lmp. qts)
5.1 liters (5.4 US qts, 4.5 lmp. qts)
Dry fill6.5 liters (6.9 US qts, 5.7 lmp. qts)
(c) Reinstall the oil filler cap.
4. START ENGINE AND CHECK FOR OIL LEAKS
5. RECHECK ENGINE OIL LEVEL

LU05L±01
B01644
P02186
Mark
P02294
P02157
P02156
± LUBRICATION (2JZ±GE)OIL PUMP
LU±9
1581 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
INSPECTION
1. INSPECT RELIEF VALVE
Coat the valve with engine oil and check that it falls smoothly
into the valve hole under its own weight.
If it doesn't, replace the relief valve. If necessary, replace the oil
pump assembly.
2. PLACE DRIVE AND DRIVEN ROTORS INTO OIL PUMP
BODY
The marks on the rotors must face up.
3. INSPECT ROTOR TIP CLEARANCE
Using a feeler gauge, measure the clearance between the drive
and driven rotors.
Standard tip clearance:
0.060 ± 0.240 mm (0.0024 ± 0.0094 in.)
Maximum tip clearance:
0.30 mm (0.0118 in.)
If the tip clearance is greater than maximum, replace the rotors
as a set.
4. INSPECT ROTOR BODY CLEARANCE
Using a feeler gauge, measure the clearance between the driv-
en rotor and pump body.
Standard body clearance:
0.100 ± 0.175 mm (0.0039 ± 0.0069 in.)
Maximum body clearance:
0.20 mm (0.0079 in.)
If the body clearance is greater than maximum, replace the ro-
tors as a set. If necessary, replace the oil pump assembly.
5. INSPECT ROTOR SIDE CLEARANCE
Using a feeler gauge and precision straight edge, measure the
clearance between the rotors and precision straight edge.
Standard side clearance:
0.030 ± 0.090 mm (0.0012 ± 0.0035 in.)
Maximum side clearance:
0.12 mm (0.0047 in.)
If the side clearance is greater than maximum, replace the ro-
tors as a set. If necessary, replace the oil pump assembly.
6. REMOVE DRIVE AND DRIVEN ROTORS

MA001±07
± MAINTENANCEOUTSIDE VEHICLE
MA±1
44 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
OUTSIDE VEHICLE
GENERAL MAINTENANCE
These are maintenance and inspection items which are considered to be the owner's responsibility.
They can be done by the owner or they can have them done at a service shop.
These items include those which should be checked on a daily basis, those which, in most cases, do not
require (special) tools and those which are considered to be reasonable for the owner to do.
Items and procedures for general maintenance are as follows.
1. GENERAL NOTES

Maintenance items may vary from country to country. Check the owner's manual supplement in which
the maintenance schedule is shown.

Every service item in the periodic maintenance schedule must be performed.

Periodic maintenance service must be performed according to whichever interval in the periodic main-
tenance schedule occurs first, the odometer reading (miles) or the time interval (months).

Maintenance service after the last period should be performed at the same interval as before unless
otherwise noted.

Failure to do even one item an cause the engine to run poorly and increase exhaust emissions.
2. TIRES
(a) Check the pressure with a gauge. If necessary, adjust.
(b) Check for cuts, damage or excessive wear.
3. WHEEL NUTS
When checking the tires, check the nuts for looseness or for missing nuts. If necessary, tighten them.
4. TIRE ROTATION
Check the owner's manual supplement in which the maintenance schedule is shown.
5. WINDSHIELD WIPER BLADES
Check for wear or cracks whenever they do not wipe clean. If necessary, replace.
6. FLUID LEAKS
(a) Check underneath for leaking fuel, oil, water or other fluid.
(b) If you smell gasoline fumes or notice any leak, have the cause found and corrected.
7. DOORS AND ENGINE HOOD
(a) Check that all doors and the tailgate operate smoothly, and that all latches lock securely.
(b) Check that the engine hood secondary latch secures the hood from opening when the primary latch
is released.