Page 444 of 1111
BR0K5±07
F02817
F02818
± BRAKEREAR SPEED SENSOR
BR±61
2169 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
REMOVAL
1. DISCONNECT SPEED SENSOR CONNECTOR
(a) Remove the seat cushion and 2 headrests.
(b) Remove the 4 bolts, 2 nuts and seatback.
Torque: 18 N´m (185 kgf´cm, 13 in.´lbf)
(c) Disconnect the speed sensor connector and pull out the
sensor wire harness with the grommet.
2. REMOVE SPEED SENSOR
(a) Remove the clamp bolt holding the sensor wire harness
to the suspension arm No. 1.
Torque: 5.0 N´m (51 kgf´cm, 44 in.´lbf)
(b) Remove the clamp nut holding the sensor wire harness
to the body.
Torque: 5.5 N´m (56 kgf´cm, 49 in.´lbf)
(c) Remove the sensor installation bolt and speed sensor
from the axle carrier.
Torque: 8.0 N´m (82 kgf´cm, 71 in.´lbf)
Page 445 of 1111
BR0K6±04
BR±62
± BRAKEREAR SPEED SENSOR
2170 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
INSTALLATION
Installation is in the reverse order of removal (See page BR±61).
HINT:
After installation, check speed sensor signal (See page DI±389).
Page 625 of 1111

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.
Page 639 of 1111

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
Page 642 of 1111

± 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
Page 646 of 1111

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.
Page 793 of 1111

SS0FE±01
± SERVICE SPECIFICATIONSSUSPENSION AND AXLE
SS±53
209 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
TORQUE SPECIFICATION
Part tightenN´mkgf´cmft´lbf
FRONT
Hub nut1031,05076
Brake caliper x Steering knuckle11 81,20087
ABS speed sensor x Steering knuckle7.88069 in.´lbf
Steering knuckle x Upper suspension arm8789064
Lower ball joint x Steering knuckle11 31,15083
Brake dust cover x Steering knuckle8.38574 in.´lbf
ABS speed sensor wire harness x Shock absorber5.05548 in.´lbf
Stabilizer bar x Stabilizer bar link5556041
Shock absorber bracket x Shock absorber1571,60011 6
Piston rod x Suspension support No.22728020
Suspension support No.1 x Body5657041
Upper suspension arm x Body5354039
Stabilizer bar link x No.2 lower suspension arm11 31,15083
Height control link x Shock absorber bracket5.45548 in.´lbf
No.2 lower suspension arm x No.1 lower suspension arm2452,500180
No.2 lower suspension arm x Lower ball joint1621,65011 9
Strut bar bracket x Body A
B58
152590
1,55043
11 2
No.2 lower suspension arm x Body9597070
Shock absorber bracket x No.2 lower suspension arm2525018
Tie rod end x Lower ball joint8789064
Stabilizer bar bracket x Body2829021
Tie rod end lock nut5657041
Axle hub lock nut1992,030147
Page 794 of 1111

SS±54
± SERVICE SPECIFICATIONSSUSPENSION AND AXLE
210 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)Part tighten
N´mkgf´cmft´lbf
REAR
Hub nut1031,05076
Brake caliper x Axle carrier1041,06577
Axle carrier x Upper suspension arm1081,10080
Backing plate x Axle carrier5960043
Drive shaft x Axle hub2892,950213
No.2 lower suspension arm x Axle carrier11 01,12081
No.1 lower suspension arm x Axle carrier7576555
Drive shaft x Differential side gear shaft6869550
Differential drain plug4950039
Differential filler plug4950039
Differential mounting boltFront
Rear123
1421,250
1,45090
105
Ring gear set boltSee page SA±73
Companion flange lock nutSee page SA±73
Differential carrier retainer set bolt2222516
Differential carrier cover set bolt4747534
Breather plug2121015
Suspension support x Body Upper side
Lower side64
18650
18547
13
Piston rod x Suspension support2728020
Upper suspension arm x Body8890065
No.1 lower suspension arm x Body7576555
No.2 lower suspension arm x Stabilizer bar link x Height control sensor link3030522
No.2 lower suspension arm x Shock absorber11 01,12081
No.2 lower suspension arm x Body11 01,12081
ABS speed sensor wire harness x Toe control link5.45548 in.´lbf
Toe control link x Axle carrier5960044
Toe control link x Body5960044
Stabilizer bar x Stabilizer bar link6566048
Stabilizer bar bracket x Body1818513
ABS speed sensor x Axle carrier7.88069 in.´lbf
Parking brake cable x Backing plate7.88069 in.´lbf
Suspension member brace x Body5051037
Differential x Propeller shaft7980558
Oil deflector x Differential carrier cover7.07062 in.´lbf