automatic transmission LEXUS GS400 2000 Service Service Manual

DIAGNOSTIC TROUBLE CODE CHECK PROCEDURE
Diagnostic Trouble
Code Check (Make a
note of and then clear)Confirmation
of SymptomsDiagnostic Trouble
Code CheckProblem Condition
Diagnostic Trouble
Code DisplayProblem symptoms
existSame diagnostic
trouble code is
displayedProblem is still occurring in the diagnostic
circuit
Normal code is
displayedThe problem is still occurring in a place
other than in the diagnostic circuit
(The diagnostic trouble code displayed
first is either for a past problem or it is a
secondary problem)
No problem
symptoms existThe problem occurred in the diagnostic
circuit in the past
Normal Code DisplayProblem symptoms
existNormal code is
displayedThe problem is still occurring in a place
other than in the diagnostic circuit
No problem
symptoms existNormal code is
displayedThe problem occurred in a place other
than in the diagnostic circuit in the past
± INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMSIN±23
23 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
2. SYMPTOM CONFIRMATION AND DIAGNOSTIC TROUBLE CODE CHECK
The diagnostic system in the LEXUS GS400/GS300 fulfills various functions. The first function is the Diag-
nostic Trouble Code Check in which a malfunction in the signal circuits to the ECU is stored in code in the
ECU memory at the time of occurrence, to be output by the technician during troubleshooting. Another func-
tion is the Input Signal Check which checks if the signals from various switches are sent to the ECU correctly.
By using these check functions, the problem areas can be narrowed down quickly and troubleshooting can
be performed effectively. Diagnostic functions are incorporated in the following systems in the LEXUS
GS400/GS300.
SystemDiagnostic Trouble
Code CheckInput Signal Check
(Sensor Check)Diagnostic Test
Mode (Active Test)
Engine (2JZ±GE)
Engine (1UZ±FE)
Automatic Transmission
ABS & Hydraulic Brake Booster Power Supply System
Vehicle Skid Control (VSC) & Brake Assist (BA) System
Power Tilt and Power Telescopic Steering Column
Supplemental Restraint System
Cruise Control System
Engine Immobiliser System
Multiplex Communication System
LEXUS Navigation System
Air Conditioning System(with check Mode)
(with check Mode)
(with check Mode)















In diagnostic trouble code check, it is very important to determine whether the problem indicated by the diag-
nostic trouble code is still occurring or occurred in the past but returned to normal at present. In addition,
it must be checked in the problem symptom check whether the malfunction indicated by the diagnostic
trouble code is directly related to the problem symptom or not. For this reason, the diagnostic trouble codes
should be checked before and after the symptom confirmation to determine the current conditions, as shown
in the table below. If this is not done, it may, depending on the case, result in unnecessary troubleshooting
for normally operating systems, thus making it more difficult to locate the problem, or in repairs not pertinent
to the problem. Therefore, always follow the procedure in correct order and perform the diagnostic trouble
code check.

IN04Q±07
IN±36
± INTRODUCTIONTERMS
36 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
TERMS
ABBREVIATIONS USED IN THIS MANUAL
AbbreviationsMeaning
ABSAnti±Lock Brake System
ACAlternating Current
ACCAccessory
ACISAcoustic Control Induction System
ACSDAutomatic Cold Start Device
A.D.D.Automatic Disconnecting Differential
A/FAir±Fuel Ratio
AHCActive Height Control Suspension
ALRAutomatic Locking Retractor
ALTAlternator
AMPAmplifier
ANTAntenna
APPROX.Approximately
A/TAutomatic Transmission (Transaxle)
AT FAutomatic Transmission Fluid
AUTOAutomatic
AUXAuxiliary
AV GAverage
AV SAdaptive Variable Suspension
BABrake Assist
BACSBoost Altitude Compensation System
BATBattery
BDCBottom Dead Center
B/LBi±Level
B/SBore±Stroke Ratio
BTDCBefore Top Dead Center
BVSVBimetallic Vacuum Switching Valve
Calif.California
CBCircuit Breaker
CCoCatalytic Converter For Oxidation
CDCompact Disc
CFCornering Force
CGCenter Of Gravity
CHChannel
COMB.Combination
CPECoupe
CPSCombustion Pressure Sensor
CPUCentral Processing Unit
CRSChild Restraint System
CTRCenter
C/VCheck Valve
CVControl Valve

± MAINTENANCEINSIDE VEHICLE
MA±3
46 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
13. ACCELERATOR PEDAL
Check the pedal for smooth operation and uneven pedal effort or catching.
14. BRAKE PEDAL (See page BR±9)
(a) Check the pedal for smooth operation.
(b) Check that the pedal has the proper reserve distance and freeplay.
(c) Check the brake booster function.
15. BRAKES
At a safe place, check that the brakes do not pull to one side when applied.
16. PARKING BRAKE (See page BR±11)
(a) Check that the lever has the proper travel.
(b) On a safe incline, check that the vehicle is held securely with only the parking brake applied.
17. AUTOMATIC TRANSMISSION ºPARKº MECHANISM
On a safe incline, check that the vehicle is held securely with the selector lever in ºPº position and all brakes
released.

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.

MA01S±01
± MAINTENANCECHASSIS
MA±7
50 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
CHASSIS
INSPECTION
1. INSPECT STEERING LINKAGE
(a) Check the steering wheel freeplay.
(See page SR±8)
(b) Check the steering linkage for looseness or damage.
Check that:

Tie rod ends do not have excessive play.

Dust seals and boots are not damaged.

Boot clamps are not loose.
2. INSPECT SRS AIRBAG
(DRIVER'S SIDE: See page RS±15)
(PASSENGER'S SIDE: See page RS±29)
3. INSPECT STEERING GEAR HOUSING OIL
Check the steering gear housing for oil leakage.
4. INSPECT LOWER BALL JOINTS AND DUST COVERS
(a) Jack up the front of the vehicle and support it with stands.
(b) Make sure the front wheels are in a straight±ahead posi-
tion, and depress the brake pedal.
(c) Jack up the lower suspension arm until there is about half
a load on the front coil spring.
(d) Inspect the dust cover for damage.
5. CHECK AUTOMATIC TRANSMISSION AND
DIFFERENTIAL
Visually check the automatic transmission and differential for oil
leakage.
If leakage is found, check for the cause and repair it.
6. REPLACE AUTOMATIC TRANSMISSION FLUID
(See page DI±318)
7. REPLACE DIFFERENTIAL OIL
(See page SA±61)

PP0N4±02
± PREPARATIONAUTOMATIC TRANSMISSION
PP±59
111 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
AUTOMATIC TRANSMISSION
SST (Special Service Tools)
09032±00100Oil Pan Seal CutterOil pan
09308±00010Oil Seal PullerExtension housing rear oil seal
09309±37010Transmission Bearing ReplacerExtension housing rear oil seal
09350±30020TOYOTA Automatic Transmission
Tool Set
(09351±32020)Stator Stopper
09950±60010Replacer Set
(09951±00350)Replacer 35
09950±70010Handle Set
(09951±07100)Handle 100
09992±00095Automatic Transmission Oil
Pressure Gauge Set
(09992±00231)Adaptor C
(09992±00271)Gauge Assy

PP0N5±02
PP±60
± PREPARATIONAUTOMATIC TRANSMISSION
11 2 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
RECOMMENDED TOOLS
09017±12301Deep Socket Wrench 30 mm .
09082±00040TOYOTA Electrical Tester.

PP0N6±01
± PREPARATIONAUTOMATIC TRANSMISSION
PP±61
11 3 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
EQUIPMENT
OBD II scan tool
Dial indicator or dial indicator with magnetic baseOutput shaft, Major bushing
Straight edge
Torque wrench

PP0N7±06
PP±62
± PREPARATIONAUTOMATIC TRANSMISSION
11 4 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
LUBRICANT
ItemCapacityClassification
Automatic transmission fluid
Dry fill
Drain and refill
8.4 liters (8.9 US qts, 7.4 Imp. qts)
1.9 liters (2.0 US qts, 1.7 Imp. qts)ATF TYPE T±IV

PP0SU±01
± PREPARATIONAUTOMATIC TRANSMISSION
PP±63
11 5 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
SSM (Special Service Materials)
08826±00090Seal Packing 1281,
THREE BOND 1281 or equivalent
(FIPG)Transmission case x Oil pan