belt LEXUS GS400 2000 Service User Guide

BE±14
± BODY ELECTRICALTROUBLESHOOTING
2315 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
w/o Driving Position Memory System:
SymptomSuspect AreaSee page
Mirror does not operate.
1. Mirror Switch
2. Wire Harness
3. Body No.2 ECU
4. Driver and Passenger Door ECUBE±176
±
DI±820
DI±856
DI±889
Mirror operates abnormally.
1. Mirror Switch
2. Mirror Motor
3. Wire Harness
4. Body No.2 ECU
5. Driver and Passenger Door ECUBE±176
BE±176
±
DI±820
DI±856
DI±889
ELECTRO CHROMIC MIRROR SYSTEM
SymptomSuspect AreaSee page
Electro Chromic Inner Mirror does not operate.
1. ECU±IG Fuse
2. Electro Chromic Inner Mirror
3. Wire HarnessBE±21
BE±182
±
Electro Chromic Outer Mirror does not operate.
1. ECU±IG Fuse
2. Electro Chromic Outer Mirror
3. Electro Chromic Inner Mirror
4. Wire HarnessBE±21
BE±182
BE±182
±
SEAT HEATER SYSTEM
SymptomSuspect AreaSee page
Seat heaters do not operate.
(Driver's and Passenger's)
1. SEAT HTR Fuse
2. Seat Heater Switch (D, P)
3. Wire Harness
4. Seat HeaterBE±21
BE±185
±
BE±185
Driver's seat heater does not operate.1. Seat Heater Switch (D, P)
2. Wire HarnessBE±185
±
Passenger's seat heater does not operate.1. Seat Heater Switch (D, P)
2. Wire HarnessBE±185
±
Seat heater temperature is too hot.Seat HeaterBE±185
FUEL LID OPENER SYSTEM
SymptomSuspect AreaSee page
Fuel lid opener system does not operate.
1. FUEL OPN Fuse
2. Fuel Lid Opener Switch
3. Fuel Lid Opener Motor
4. Wire HarnessBE±21
BE±188
BE±188
±
AUDIO SYSTEM
SymptomSuspect AreaSee page
Audio system abnormal operation.TROUBLESHOOTINGSBE±196
CLOCK SYSTEM
SymptomSuspect AreaSee page
Passenger seat belt warning system does not light up.TROUBLESHOOTING NO.1BE±227
Clock will not operate.TROUBLESHOOTING NO.1BE±227
Clock loses or gains time.TROUBLESHOOTING NO.2BE±227

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.

I01360
Fuel Tank

Fuel Main
Sender Gauge
Fuel Tank

Fuel Sub
Sender Gauge
Occupant Detection Sensor
(Passenger seat belt
warning sensor)
Engine Oil Level
Warning Sensor Engine Oil Level
Warning Sensor
Park/ Neutral
Position Switch
Low Oil Pressure
Warning Switch
Park/ Neutral
Position Switch
Low Oil Pressure
Warning Switch
GS300GS400 Light Failure Sensor
± BODY ELECTRICALCOMBINATION METER
BE±81
2382 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)

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

I04105
Dark
(10k W)Bright
(0W)
4
5
I01322
Battery Ignition
SwitchWarning Light
2 1 Wire Harness Side
I01323
1 2 OFF
ON
I01328
Battery Ignition
SwitchWarning Light
2 1 Wire Harness Side
I04107
12
4
OFF
ON BE±102
± BODY ELECTRICALCOMBINATION METER
2403 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
30. INSPECT LIGHT CONTROL RHEOSTAT OPERATION
Gradually, turn the rheostat knob from the bright side to dark
side and check that the resistance decreases from 10 kW to 0
W between terminal 4 and 5. (Rheostat knob turned to clock-
wise)
If operation is not as specified, replace the rheostat light control.
31. INSPECT WINDOW WASHER LEVEL WARNING
LIGHT
(a) Disconnect the connector from the warning switch and
ground terminal on the wire harness side connector.
(b) Engine running and check that the warning light lights up.
If the warning light does not light up, inspect the bulb or wire har-
ness.
32. INSPECT WINDOW WASHER LEVEL WARNING
SWITCH CONTINUITY
(a) Check that no continuity exists between the terminals with
the switch OFF (float up).
(b) Check that continuity exists between the terminals with
the switch ON (float down).
If operation is not as specified, replace the switch or inspect
ground point.
33. INSPECT SEAT BELT WARNING LIGHT
(a) Disconnect the connector from the retractor 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, inspect the bulb or wire har-
ness.
34. INSPECT SEAT BELT BUCKLE SWITCH CONTINUITY
(a) Check that continuity exists between the terminals 1 and
4 on the switch side connector with the switch ON (belt
fastened).
(b) Check that continuity exists between the terminals 2 and
4 on the switch side connector with the switch OFF (belt
unfastened).
If operation is not as specified, replace the switch.

I04108
Wire Harness Side
I04109
Press
Sensing part
± BODY ELECTRICALCOMBINATION METER
BE±103
2404 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
35. INSPECT SEAT BELT BUCKLE SWITCH CIRCUIT
Driver side: (See page DI±830)
Passenger side: (See page DI±785)
Disconnect the switch connector and inspect the connector on
wire harness side, as shown.
Tester connectionConditionSpecified condition
4 ± GroundConstantContinuity
If continuity is not as specified, inspect the circuits connected
to other parts.
36. Passenger seat only:
INSPECT SEAT BELT WARNING OCCUPANT DETEC-
TION SENSOR CONTINUITY
Check that continuity exists between the terminals 1 and 2
when pressing the sensing part.
If operation is not as specified, replace the sensor.
37. Passenger seat only:
INSPECT SEAT BELT WARNING OCCUPANT DETEC-
TION SENSOR CIRCUIT (See page DI±785)

Z05962
B02027
Turn
B02028
Move
B01995
Type A
A
Type BB
AB
Z05963
CORRECT WRONG WRONG CH±2
± CHARGING (2JZ±GE)CHARGING SYSTEM
1604 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
5. INSPECT DRIVE BELT
HINT:
A belt tensioner is used, so checking the belt tension is not nec-
essary.
(a) Visually check the drive belt for excessive wear, frayed
cords, etc.
If necessary, replace the drive belt.
HINT:

Cracks on the rib side of a drive belt are considered ac-
ceptable. If the drive belt has chunks missing from the
ribs, it should be replaced.

The drive belt tension can be released by turning the belt
tensioner clockwise.
(b) Check the belt tensioner operation.

Check that the belt tensioner moves downward
when the drive belt is pressed down at the points in-
dicated in the illustration with approx. 98 N (10 kgf,
22.0 lbf) of force.

Check the alignment of the belt tensioner pulley to
make sure the drive belt will not slip off the pulley.
If necessary, replace the belt tensioner.

Check that the arrow mark on the belt tensioner falls
within area A of the scale.
If it is outside area A, replace the drive belt.
HINT:

When a new belt is installed, it should lie within area B. If
not, the drive belt is not correct.

After installing a drive belt, check that it fits properly in the
ribbed grooves.

Check by hand to confirm that the belt has not slipped out
of the groove on the bottom of the pulley.
6. VISUALLY CHECK GENERATOR WIRING AND
LISTEN FOR ABNORMAL NOISES
(a) Check that the wiring is in good condition.
(b) Check that there is no abnormal noise from the generator
while the engine is running.