brake LEXUS GS400 2000 Service User Guide

I01260
21
3 42
41
3
I01200
2 1
35
2 5
1 3
I04037
Wire Harness Side
h±10±1±A
± BODY ELECTRICALHEADLIGHT AND TAILLIGHT SYSTEM
BE±41
2342 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
11. INSPECT HEADLIGHT DIMMER ( DAYTIME RUNNING
LIGHT NO.2) RELAY CONTINUITY
ConditionTester connectionSpecified condition
Constant1 ± 4
2 ± 4Continuity
Apply B+ between
terminals 2 and 4.1 ± 3 ± 4Continuity
If continuity is not as specified, replace the relay.
12. INSPECT HEADLIGHT DIMMER (DAYTIME RUNNING
LIGHT NO.2) RELAY CIRCUIT
(See page BE±21)
13. INSPECT TAILLIGHT CONTROL RELAY CONTINUITY
ConditionTester connectionSpecified condition
Constant1 ± 2Continuity
Apply B+ between
terminals 1 and 2.3 ± 5Continuity
If continuity is not as specified, replace the relay.
14. INSPECT TAILLIGHT CONTROL RELAY CIRCUIT
(See page DI±845 and BE±21)
15. INSPECT DAYTIME RUNNING LIGHT MAIN RELAY
CIRCUIT
Disconnect the connector from the relay and inspect the con-
nector on the wire harness side.
Tester connectionConditionSpecified condition
2 ± GroundLight control switch OFF or TAILNo continuity
2 ± GroundLight control switch HEADContinuity
4 ± GroundParking brake switch OFF
(Parking brake pedal released)No continuity
4 ± GroundParking brake switch ON
(Parking brake pedal depressed)Continuity
6 ± GroundConstantContinuity
8 ± GroundHeadlight dimmer switch LOW beamNo continuity

BE0HH±07
I01359
Brake Master Cylinder

Brake Fluid Level
Warning Switch
Combination Meter
and Telltale Light
Assembly
Airbag Sensor Assembly Parking Brake Switch
Driver Side
Junction Block

GAUGE Fuse

SRS±B FuseIgnition Switch
ECM
Washer Tank

Washer Level
Warning Switch Engine Room No.1
Junction Block

MPX±B Fuse
Seat Belt Buckle Switch
Rheostat Light Control
ABS, TRAC and VSC ECU
Clock Assembly

Passenger Seat Belt
Waning Light
BE±80
± BODY ELECTRICALCOMBINATION METER
2381 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
COMBINATION METER
LOCATION
The vehicle shown in this illustration is ºGS400º.
All components of ºGS300º other than the ones used for engine are same as ºGS400º.

I04250

Combination Meter Wiring Circuit ± 1
:Speedometer
:Tachometer
:Fuel Receiver Gauge
:Engine Coolant
Temperature
Receiver Gauge
Speed Control Unit
CLOCK
to GAUGE Fuse
to MPX±B Fuse
to SRS Fuse
Tilt and Telescopic ECU
Body ECU NO.2ECM (GS400)
Ignitor (GS300)
Fuel Main Sender GaugeGround
Fuel Sub Sender Gauge
Light Control Rheostat
Illuminations
ABS, TRAC and VSC ECU
ABS, TRAC and VSC ECU Speed Signal Passenger seat
belt warning
Rr LIGHTS
SEAT BELT
OIL PRESS
OIL LEVEL
DOOR IG+
SRS +BA/T P
A/T R
A/T N
A/T D
A/T 4
A/T 3
A/T 2
A/T L
CRUISE MPX+BIG+IG+
5V
+B
to ECUto
PANEL
Fuse B4
B5
B6
B9
A5
A17A3A8 B16
LCDECU S
T
F
E
Power Source
Brake
Buzzer A11A2 A1 A6
B1
B13
B14A4
B22 ECU
ECU
ECU
S
T
F
E
CHARGE
FUEL LVL
ECT PWR
ECT SNOW TAIL or HEAD
Ground IG+IG+ IG+ IG+
+B
± BODY ELECTRICALCOMBINATION METER
BE±83
2384 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)

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)

I04253

Meter Circuit Plate ± 2
Combination Meter ECU
SLIP Indicator
TRAC OFF Indicator
Window Washer Level Warning
ABS Warning
VSC Warning
Brake Fluid Level Warning
ECT SNOW Indicator
Low Oil Pressure Warning
ECT PWR Indicator
Discharge Warning
CRUISE MAIN Indicator
Seat Belt Warning
Rear Light Indicator
Headlight Leveling Indicator
SRS Warning
Open Door Warning
Fog Light IndicatorA/T 2 Indicaor
Engine Oil Level Indicator
Malfunction Indicator
Fuel Level Indicator
Headlight Indicator (USA)
Taillight Indicator (CANADA) ODO/
TRIP
Display
PanelIG+
SLIP
TRC OFF
WASHER
ABS
VSC
BRAKE
ECT SNOW
OIL P
ECT PWR
CHARGE
CRUISE
SEAT BELT
Rr LIGHT
HEAD LVL
AIRBAG
SRS +B
DOOR
FR FOG
COM1
SEG30
TEST1
TEST2
TEST3
GroundCHECK
ENG
IG+
FUEL
IG+
BEAM±
BEAM+ SRS +BTAIL A/T R
A/T L
A/T N
A/T D
OIL LVLDIM+
A/T 2
A/T 3
A/T 4F12
A/T PF11
F10
F9
F8
F5
F4
F2
F1
C7
C5
C3
D12
D8 E11
E10
E9
E8
E7
E6
J1
J33
D6
D4Hi±Beam Indicator
D2 E20
E19
E18
E17
E16
E15
E14
E13
E12
E3
E1 E5
E4A/T 3 Indicaor
A/T 4 Indicaor
A/T P Indicaor
A/T R Indicaor
A/T L Indicaor
A/T N Indicaor
A/T D Indicaor
T1
T2
T3
T4
~~
D10 BE±88
± BODY ELECTRICALCOMBINATION METER
2389 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)

I04079
Connector ºCº Connector ºDº
Connector ºFº Connector ºEº
Connector ºGº
1 131 13
1 201 12
± BODY ELECTRICALCOMBINATION METER
BE±93
2394 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
2. INSPECT COMBINATION METER CIRCUIT PLATE
Warning light circuit plate:
(a) Remove meter cover.
(b) Disconnect connectors ºCº, ºDº, ºEº, ºFº and ºGº from the
meter circuit plate and inspect the connectors on the wire
harness side as shown in the table.
Tester connectionCheck indicator lightSpecified condition
D10 (+) ± D12 (±)Fuel level warning lightContinuity
D6 (+) ± D8 (±)Headlight indiactor light (USA)
Taillight indiactor light (CANADA)Continuity
D2 (+) ± D4 (±)Hi±beam indicator lightContinuity
C3 (+) ± C7 (±)Engine oil level warning lightContinuity
C3 (+) ± C5 (±)Malfunction indicator lightContinuity
E19 (±) ± E20 (+)Slip warning lightContinuity
E18 (±) ± E20 (+)TRAC OFF indicator lightContinuity
E17 (±) ± E20 (+)Window washer level warning lightContinuity
E16 (±) ± E20 (+)ABS warning lightContinuity
E15 (±) ± E20 (+)VSC OFF indicator lightContinuity
E14 (±) ± E20 (+)Brake warning lightContinuity
E13 (±) ± E20 (+)ECT SNOW indicator lightContinuity
E12 (±) ± E20 (+)Low oil pressure warning lightContinuity
E11 (±) ± E20 (+)ECT PWR indicator lightContinuity
E10 (±) ± E20 (+)Discharge warning lightContinuity
E9 (±) ± E20 (+)CRUISE MAIN indicator lightContinuity
E8 (±) ± E20 (+)Seat belt warning lightContinuity
E7 (±) ± E20 (+)Rear Lights warning lightContinuity
E6 (±) ± E20 (+)Headlight leveling indiactorContinuity
E4 (+) ± E5 (±)SRS warning lightContinuity
E3 (±) ± E4 (+)Open door warning lightContinuity
F4 (±) ± F12 (+)A/T shift indicator light (L)Continuity
F11 (±) ± F12 (+)A/T shift indicator light (2)Continuity
F10 (±) ± F12 (+)A/T shift indicator light (3)Continuity
F8 (±) ± F12 (+)A/T shift indicator light (P)Continuity

I01278
I01279
Battery Ignition
SwitchWarning Light
I04095
OFF
ON
I04096
± BODY ELECTRICALCOMBINATION METER
BE±99
2400 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
17. INSPECT LOW OIL PRESSURE SWITCH CONTINUITY
(a) Disconnect the connector from the switch.
(b) Check that continuity exists between terminal and ground
with the engine stopped.
(c) Check that no continuity exists between terminal and
ground with the engine running.
HINT:
Oil pressure should be over 24.5 kPa (0.25 kgf/cm
2, 3.55 psi).
If operation is not as specified, replace the switch.
18. INSPECT BRAKE WARNING LIGHT
(a) Disconnect the connector from the brake fluid warning
switch.
(b) Release the parking brake pedal.
(c) Connect the terminals on the wire harness side of the lev-
el warning switch connector.
(d) Start the engine, check that the warning light lights up.
If the warning light does not light up, test the bulb or wire har-
ness.
19. INSPECT BRAKE FLUID LEVEL WARNING SWITCH
CONTINUITY
(a) Remove the reservoir tank cap and strainer.
(b) Disconnect the connector.
(c) Check that no continuity exists between the terminals with
the switch OFF (float up).
(d) Use siphon, etc. to take fluid out of the reservoir tank.
(e) Check that continuity exists between the terminals with
the switch ON (float down)
(f) Pour the fluid back in the reservoir tank.
If operation is not as specified, replace the switch.
20. INSPECT BRAKE FLUID LEVEL WARNING SWITCH
CIRCUIT (See page DI±835)
21. INSPECT PARKING BRAKE SWITCH CONTINUITY
(a) Check that continuity exists between the terminal and
switch body with the switch ON (switch pin released).
(b) Check that no continuity exists between the terminal and
switch body with the switch OFF (switch pin pushed in).
If operation is not as specified, replace the switch or inspect
ground point.
22. INSPECT PARKING BRAKE SWITCH CIRCUIT
(See page DI±796)

BR0J9±01
± BRAKEBRAKE SYSTEM
BR±1
2109 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
BRAKE SYSTEM
GENERAL DESCRIPTION

Care must be taken to replace each part properly as it could affect the performance of the brake
system and result in a driving hazard. Replace the parts with parts of the same part number or
equivalent.

It is very important to keep parts and the area clean when repairing the brake system.

If the vehicle is equipped with a mobile communication system, refer to the precautions in the
IN section.

F01619
BR0JD±03
F01620
Adjusting Nut
Lock Nut
± BRAKEPARKING BRAKE PEDAL
BR±11
2119 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
PARKING BRAKE PEDAL
ON±VEHICLE INSPECTION
1. CHECK PARKING BRAKE PEDAL TRAVEL
Depress the parking brake pedal all the way and count the num-
ber of clicks.
Parking brake lever travel at 294 N (30 kgf, 66.1 Ibf):
7 ± 9 clicks
2. IF NECESSARY, ADJUST PARKING BRAKE
HINT:
Before adjusting the parking brake, make sure that the rear
brake shoe clearance has been adjusted. For shoe clearance
adjustment see page BR±37.
(a) Loosen the lock nut and turn the adjusting nut until the
pedal travel is correct.
(b) Tighten the lock nut.
Torque: 5.4 N´m (55 kgf´cm, 48 in.´lbf)

BR0JE±03
F07241
No. 1 Safety Pad
No. 1 Under Cover
Front Door Scuff Plate End Pad
Parking Brake Switch
Parking Brake Pedal
AssemblyParking Brake WireAdjusting NutLock Nut
13 (130, 9)
5.4 (55, 48 in.´lbf)
No. 7 Heater to Register Duct
N´m (kgf´cm, ft´lbf) : Specified torque BR±12
± BRAKEPARKING BRAKE PEDAL
2120 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
COMPONENTS