2000 LEXUS GS400 coolant temperature

I04259
I04260
I04261
I04262
I04263
± BODY ELECTRICALCOMBINATION METER
BE±91
2392 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
5. REMOVE METER GLASS
Remove the 3 screws and the meter glass.
6. REMOVE DECORATION PLATE
7. REMOVE SPEEDOMETER
Remove the 2 screws.
8. REMOVE TACHOMETER, FUEL RECEIVER GAUGE
AND ENGINE COOLANT TEMPERATURE RECEIVER
GAUGE
Remove the 4 screws.
9. REMOVE COLD CATHODE TUBE WITH PLATE

I04080
Connector
ºOº, ºPº, ºQº, ºRº BE±94
± BODY ELECTRICALCOMBINATION METER
2395 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)F5 (±) ± F12 (+)
A/T shift indicator light (R)Continuity
F2 (±) ± F12 (+)A/T shift indicator light (N)Continuity
F1 (±) ± F12 (+)A/T shift indicator light (D)Continuity
G1 (+) ± G5 (±)Left turn signal indicator lightContinuity
G6 (+) ± G5 (±)Right turn signal indicator lightContinuity
If circuit is not as specified, replace the bulb or circuit plate.
3. INSPECT COMBINATION METER CIRCUIT PLATE
From combination meter ECU to gauges:
TerminalResistance (W)
O1 ± O3
(Engine coolant temperature receiver gauge)Approx. 164.2
O2 ± O4
(Engine coolant temperature receiver gauge)Approx. 151.8
P1 ± P4 (Tachometer)Approx. 164.2
P2 ± P3 (Tachometer)Approx. 151.8
Q1 ± Q4 (Speedometer)Approx. 164.2
Q2 ± Q3 (Speedometer)Approx. 151.8
R1 ± R4 (Fuel receiver gauge)Approx. 164.2
R2 ± R3 (Fuel receiver gauge)Approx. 151.8
If circuit is not as specified, inspect the gauge or meter.
Then recheck system.
If circuit is not as specified, replace the circuit plate.

I04091
F
E1
2
1/2
I04094
A
D
C
B
I01277
Battery Ignition
SwitchWarning Light
Wire Harness Side
1 BE±98
± BODY ELECTRICALCOMBINATION METER
2399 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
13. INSPECT FUEL SUB SENDER GAUGE RESISTANCE
Measure the resistance between terminals 1 and 2 for each
float position.
Float position mm (in.)Resistance (W)
F: Approx. 9.5 (0.37) ± 3 (0.12)Approx. 2.0 ± 1.0
1/2: Approx. 110.5 (4.35) ± 3 (0.12)Approx. 33.0 ± 3.0
E: Approx. 206.5 (8.13) ± 3 (0.12)Approx. 61.3 ± 1.0
If resistance value is not as specified, replace the sub sender
gauge.
14. INSPECT ENGINE COOLANT TEMPERATURE RE-
CEIVER GAUGE OPERATION (See page DI±754)
15. INSPECT ENGINE COOLANT TEMPERATURE RE-
CEIVER GAUGE RESISTANCE
Measure the resistance between terminals with fixing pointer to
the stopper.
Tester connectionResistance (W)
A ± B140 ± 185
C ± D130 ± 175
If resistance value is not as specified, replace the receiver
gauge.
HINT:
This circuit includes the diode.
If resistance value is not as specified, replace the receiver
gauge.
16. INSPECT LOW OIL PRESSURE WARNING LIGHT
(a) Disconnect the connector from the warning switch and
ground terminal on the wire harness side connector.
(b) Turn the ignition switch ON and check that the warning
light lights up.
If the warning light does not light up, test the bulb.

B01900
CO0AD±03
B00922
ECT
Switch
Connector
B02072
B02073
Ammeter
Battery(+)
(±)
CO±24
± COOLING (2JZ±GE)ELECTRIC COOLING FAN
1562 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
ELECTRIC COOLING FAN
ON±VEHICLE INSPECTION
1. CHECK COOLING FAN OPERATION WITH LOW
TEMPERATURE (Below 83°C (181°F))
(a) Turn the ignition switch ON.
(b) Check that the cooling fan stops.
If not, check the cooling fan relay and ECT switch, and check
for a separated connector or severed wire between the cooling
fan relay and ECT switch.
(c) Disconnect the ECT switch connector.
(d) Check that the cooling fan rotates.
If not, check the fuses, radiator fan main relay, cooling fan relay,
cooling fan, and check for a short circuit between the cooling
fan relay and ECT switch.
(e) Reconnect the ECT switch connector.
2. CHECK COOLING FAN OPERATION WITH HIGH
TEMPERATURE (Above 93°C (199°F))
(a) Start the engine, and raise coolant temperature to above
93°C (199°F).
HINT:
Coolant temperature is the detected value by the ECT switch
on the radiator lower tank.
(b) Check that the cooling fan rotates.
If not, replace the ECT switch.
3. INSPECT COOLING FANS
(a) Disconnect the cooling fan connector.
(b) Connect battery and ammeter to the cooling fan connec-
tor.
(c) Check that the cooling fan rotates smoothly, and check
the reading on the ammeter.
Standard amperage: 8.5 ± 11.5 A at 20°C (68°F)
(d) Reconnect the cooling fan connector.

B02035
ECT Switch
Connector
ECT
Switch
O±Ring
CO0AJ±01
P05962
Ohmmeter
± COOLING (2JZ±GE)ENGINE COOLANT TEMPERATURE (ECT) SWITCH
CO±31
1569 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
ENGINE COOLANT
TEMPERATURE (ECT) SWITCH
INSPECTION
1. DRAIN ENGINE COOLANT
2. REMOVE ECT SWITCH
(a) Disconnect the connector.
(b) Remove the ECT switch.
(c) Remove the O±ring from the ECT switch.
3. INSPECT ECT SWITCH
(a) Using an ohmmeter, check that there is no continuity be-
tween the terminals when the coolant temperature is
above 93°C (199°F).
If there is continuity, replace the switch.
(b) Using an ohmmeter, check that there is continuity be-
tween the terminals when the coolant temperature is be-
low 83°C (181°F).
If there is no continuity, replace the switch.
4. REINSTALL ECT SWITCH
(a) Install a new O±ring to the ECT switch.
(b) Install the ECT switch.
(c) Connect the connector.
5. REFILL WITH ENGINE COOLANT
6. START ENGINE AND CHECK FOR COOLANT LEAKS

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)

MA003±06
MA±4
± MAINTENANCEUNDER HOOD
47 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
UNDER HOOD
GENERAL MAINTENANCE
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. WINDSHIELD WASHER FLUID
Check that there is sufficient fluid in the tank.
3. ENGINE COOLANT LEVEL
Check that the coolant level is between the ºFULLº and ºLOWº lines on the see±through reservoir.
4. RADIATOR AND HOSES
(a) Check that the front of the radiator is clean and not blocked with leaves, dirt or bugs.
(b) Check the hoses for cracks, kinks, rot or loose connections.
5. BATTERY ELECTROLYTE LEVEL
Check that the electrolyte level of all battery cells is between the upper and lower level lines on the case.
6. BRAKE FLUID LEVEL
Check that the brake fluid levels are near the upper level line on the see±through reservoirs.
7. ENGINE DRIVE BELT
Check drive belt for fraying, cracks, wear or oiliness.
8. ENGINE OIL LEVEL
Check the level on the dipstick with the engine turned off.
9. POWER STEERING FLUID LEVEL

Check the level on the dipstick.

The level should be in the ºHOTº or ºCOLDºrange depending on the fluid temperature.
10. AUTOMATIC TRANSMISSION FLUID LEVEL
(a) Park the vehicle on a level surface.
(b) With the engine idling and the parking brake applied, shift the selector into all positions from ºPº to ºLº,
and then shift into ºPº position.
(c) Pull out the dipstick and wipe off the fluid with a clean rag. Re±insert the dipstick and check that the
fluid level is in the HOT range.
(d) Do this check with the fluid at normal driving temperature (70 ± 80°C, 158 ± 176°F).
HINT:
Wait until the engine cools down (approx. 30 min.) before checking the fluid level after extended driving at
high speeds, in hot weather, in heavy traffic or pulling a trailer.
11. EXHAUST SYSTEM
If any change in the sound of the exhaust or smell of the exhaust fumes is noticed, have the cause located
and corrected.

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