turn signal LEXUS GS400 2000 Service User Guide

Clock (Passenger seat belt warning light)
Tilt and telescopic ECU
Fuel main sender gauge
Fuel sub sender gauge
ABS, TRAC and VSC ECU (Speed signal)
Speed control unit
Headlight dimmer switch
Ground
Window washer level warning switch
Body control No.2 ECU
ECM
ABS, TRAC and VSC ECU (VSC warning light)
ABS, TRAC and VSC ECU (SLIP warning light)
ABS, TRAC and VSC ECU (TRAC OFF warning light)
ABS, TRAC and VSC ECU (ABS warning light)
ABS, TRAC and VSC ECU (Brake warning light)
GAUGE fuse
Turn signal flasher (Left turn side)
Turn signal flasher (Right turn side)
Light control rheostat (+B)
Light control rheostat (Signal)
Light control rheostat (Ground)
PANEL fuse
Airbag sensor assembly
MPX+B fuse
DOME+B fuse
HEAD±RH fuse
Igniter
Headlight beam leveling control ECU
Ground
Telltale light assembly (IG+)
Telltale light assembly (ODO/TRIP switch)
Telltale light assembly (Right turn signal)
Telltale light assembly (RESET switch)
Telltale light assembly (Left turn signal)
GroundWiring connector side No.1
1
1
2
3
4
5
6
7
8
10
11
12
13
14
15
16
17
1 1
1
2
3
4
5
6
9
12
13
14
15
16
18
22
1 1
1
3
4
8
9
10 U B A
± BODY ELECTRICALCOMBINATION METER
BE±85
2386 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)

I04252
Engine
Coolant
Temperature
Receiver
Gauge
Tachometer
Speedometer
Fuel
Receiver
GaugeRight Turn Indicator Left Turn Indicator
ODO/TRIP Switch
RESET Switch TECOS+
TESIN+
TECOS± TESIN±
TACOS+
TASIN±
TASIN+
TACOS±
SPCOS±
SPSIN+
SPSIN±
SPCOS+
FUCOS±
FUSIN+TURN L
Power
Earth
TURN R
ODO/TRIP
RESET
HEAT±
Signal
Earth
Thermistor
SRS +B
C/C ±
C/C +
HEAT±
SRS +B Power
Earth O1
O2
O3
O4
P1
P2
P3
P4
Q1
Q2
Q3
Q4
R1
R2
R3G2 G1
G3
G4
G5
G6
G7
G8
L1
L2
L3
L4
L8
L12
K1
K3
K4
R4FUSIN±
FUCOS+C/C ±
C/C +K8
K12 Combination Meter ECU
Meter Circuit Plate ± 1
± BODY ELECTRICALCOMBINATION METER
BE±87
2388 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)

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.

I04081
Connector ºGº
Connector ºUº
I04082
± BODY ELECTRICALCOMBINATION METER
BE±95
2396 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
4. INSPECT COMBINATION METER CIRCUIT PLATE
From combination meter ECU to telltale light assem-
bly:
Disconnect connector ºGº and ºUº from the meter circuit plate
and inspect the connectors on the wire harness side as follows.
Tester connectionSpecified condition
G1 ± U9Continuity
G3 ± U1Continuity
G5 ± U10Continuity
G6 ± U4Continuity
G7 ± U3Continuity
G8 ± U8Continuity
If circuit is not as specified, replace the circuit plate.
5. INSPECT TELLTALE LIGHT ASSEMBLY CONTINUITY
Switch positionTester connectionCondition
ODO/ TRIP switch Free3 ± 10No continuity
ODO/ TRIP switch
Pushed in3 ± 10Continuity
RESET switch Free8 ± 10No continuity
RESET switch Pushed in8 ± 10Continuity
Turn signal switch RIGHT4 ± 10Continuity
Turn signal switch LEFT9 ± 10Continuity
If continuity is not as specified, replace the telltale light assem-
bly.

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.

MA002±06
MA±2
± MAINTENANCEINSIDE VEHICLE
45 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
INSIDE 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. LIGHTS
(a) Check that the headlights, stop lights, taillights, turn signal lights, and other lights are all working.
(b) Check the headlight aiming.
3. WARNING LIGHTS AND BUZZERS
Check that all warning lights and buzzers function properly.
4. HORN
Check that it is working.
5. WINDSHIELD GLASS
Check for scratches, pits or abrasions.
6. WINDSHIELD WIPER AND WASHER
(a) Check operation of the wipers and washer.
(b) Check that the wipers do not streak.
7. WINDSHIELD DEFROSTER
Check that air comes out from the defroster outlet when operating the heater or air conditioner.
8. REAR VIEW MIRROR
Check that it is mounted securely.
9. SUN VISORS
Check that they move freely and are mounted securely.
10. STEERING WHEEL
Check that it has the specified freeplay. Be alert for changes in steering condition, such as hard steering,
excessive freeplay or strange noises.
11. SEATS
(a) Check that all front seat controls such as seat adjusters, seatback recliner, etc. operate smoothly.
(b) Check that all latches lock securely in any position.
(c) Check that the locks hold securely in any latched position.
(d) Check that the head restraints move up and down smoothly and that the locks hold securely in any
latches position.
(e) For folding±down rear seat backs, check that the latches lock securely.
12. SEAT BELTS
(a) Check that the seat belt system such as the buckles, retractors and anchors operate properly and
smoothly.
(b) Check that the belt webbing is not cut, frayed, worn or dameged.

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:

SR0X0±01
F01848Matchmarks
F01849Screw Extractor
F09385
± STEERINGPOWER TILT AND POWER TELESCOPIC STEERING
COLUMNSR±13
2183 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
DISASSEMBLY
NOTICE:
When using a vise, do not overtighten it.
1. REMOVE TRANSPONDER KEY COIL
Remove the screw and transponder key coil.
2. REMOVE KEY CYLINDER LAMP ILLUMINATION
3. REMOVE NO.2 INTERMEDIATE SHAFT ASSEMBLY
(a) Place matchmarks on the No.2 shaft and main shaft.
(b) Remove the bolt and No.2 intermediate shaft assembly.
4. REMOVE COLUMN UPPER BRACKET
(a) Using a centering punch, mark the center of the 2 ta-
pered±head bolts.
(b) Using a 4±5 mm (0.16±0.20 in.) drill, drill into the 2 bolts.
(c) Using a screw extractor, remove the 2 bolts and column
upper bracket.
5. REMOVE COLUMN TUBE SUPPORT
(a) Remove the bolt and column tube support.
(b) Remove the tube support with tube attachment.
(c) Remove the tube attachment from the tube support.
6. REMOVE TURN SIGNAL BRACKET
Remove the 3 bolts and turn signal bracket.
7. REMOVE STEERING COLUMN PROTECTOR
Remove the 2 bolts and steering column protector.
8. REMOVE TILT SLIDER ASSEMBLY
(a) Using a hexagon wrench, remove the 4 bolts, 2 washers
and tilt slider assembly.
(b) Remove the 4 bushings, 2 plates from tilt slider assembly.
9. REMOVE NO.1 BRACKET
Remove the bolt and No.1 bracket.
10. REMOVE NO.2 BRACKET
Remove the bolt and No.2 bracket.
11. REMOVE TILT AND TELESCOPIC ECU
Remove the 2 bolts and tilt and telescopic ECU.

SR0X1±01
F09385
± STEERINGPOWER TILT AND POWER TELESCOPIC STEERING
COLUMNSR±15
2185 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
REASSEMBLY
NOTICE:
When using a vise, do not overtighten it.
1. INSTALL TILT AND TELESCOPIC ECU
Install the tilt and telescopic ECU with the 2 screws.
2. INSTALL NO.2 BRACKET
Install the No.2 bracket with the bolt.
3. INSTALL NO.1 BRACKET
Install the No.1 bracket with the bolt.
4. INSTALL TILT SLIDER ASSEMBLY
(a) Install 2 new plates and 4 new bushings to the tilt slider
assembly in the direction shown in the illustration.
HINT:
Install the bushings with their cuts facing downward.
(b) Using a hexagon wrench, install the tilt slider assembly
with the 2 washers and 4 bolts.
Torque: 23 N´m (230 kgf´cm, 17 ft´lbf)
HINT:

When replacing a tilt slider assembly with new one, apply
grease on the removed tilt slider assembly to the shaft of
the new tilt slider assembly.

Install the tilt slider assembly with the bolt portion of the
tilt slider faced downward.

Do not let the grease be stuck on the thread part of the bolt
in order to prevent the bolt from slipping.
5. INSTALL STEERING COLUMN PROTECTOR
Install the steering column protector.
6. INSTALL TURN SIGNAL BRACKET
Install the turn signal bracket with the 3 bolts.
7. INSTALL COLUMN TUBE SUPPORT
NOTICE:
If the attachment or support is deformed, replace it with a
new one.
(a) Install the tube attachment to the tube support.
(b) Install the column tube support with the bolt.
Torque: 20 N´m (204 kgf´cm, 15 ft´lbf)
NOTICE:
Make sure to install the support facing the correct direction
(See page SR±9).

Tighten the bolt while holding the support to prevent
it turning too.

Be sure to tighten the bolt with the specified torque.

F09281
No.2 Intermediate Shaft
Assembly
Tilt and Telescopic ECUNo.2 BracketSteering Column
Protector
No.1 Bracket Column Tube SupportIgnition Switch
Tapered±Head Bolt
Tilt Steering Gear
Assembly with MotorTurn Signal
Bracket Key Interlock
SolenoidKey Unlock Warning
Switch
Key Cylinder
Illumination
Key Cylinder
35 (360, 26)
N´m (kgf´cm, ft´lbf) : Specified torque

Non±reusable part
20 (204, 15)
Tube Attachment
Column Upper
BracketTransponder Key coil
Transponder Key
Amplifier

Plate
Tilt Slider
Assembly23 (230, 17)



Bushing

23 (230, 17)

Plate

Bushing
Washer
Washer
SR±10± STEERINGPOWER TILT AND POWER TELESCOPIC STEERING
COLUMN
2180 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)