2000 LEXUS GS400 wiring

D00752
D00753
D00909
D00916
D00909
AT±6
± AUTOMATIC TRANSMISSIONATF TEMPERATURE SENSOR
1954 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
4. REMOVE OIL STRAINER
NOTICE:
Be careful as some fluid will come out of the oil strainer.
(a) Remove the 4 bolts and oil strainer.
(b) Remove the 3 gaskets from the oil strainer.
5. REMOVE SOLENOID WIRING WITH ATF TEMPERA-
TURE SENSOR
(a) Disconnect the ATF temperature sensor.
(b) Remove the bolt and clamp.
(c) Disconnect the 7 connectors from the solenoid valves.
(d) Remove the bolt and pull out the solenoid connector.
6. INSTALL SOLENOID WIRING WITH ATF TEMPERA-
TURE SENSOR
(a) Install the solenoid connector with the bolt.
Torque: 5.4 N´m (55 kgf´cm, 48 in.´lbf)
(b) Connect the 7 connectors to the solenoid valves.
(c) Install the clamp with the bolt.
Torque: 6.4 N´m (65 kgf´cm, 56 in.´lbf)
(d) Connect the ATF temperature sensor.

AT05Z±01
D00754
D01741
Spring Check Ball Body AT±8
± AUTOMATIC TRANSMISSIONVALVE BODY ASSEMBLY
1956 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
VALVE BODY ASSEMBLY
ON±VEHICLE REPAIR
CAUTION:
When working with FIPG material, you must observe the follow-
ing items.

Using a razor blade and gasket scraper, remove all the old
FIPG material from the gasket surfaces.

Thoroughly clean all components to remove all the loose
material.

Clean both sealing surfaces with a non±residue solvent.

Apply FIPG in an approx. 1 mm (0.04 in.) wide bead along
the sealing surface.

Parts must be assembled within 10 minutes of application.
Otherwise, the FIPG material must be removed and reap-
plied.
1. REMOVE DRAIN PLUG WITH GASKET AND DRAIN
AT F
2. REMOVE OIL PAN (See page AT±5)
3. EXAMINE PARTICLES IN PAN (See page AT±5)
4. REMOVE OIL STRAINER (See page AT±5)
5. REMOVE SOLENOID WIRING WITH ATF TEMPERA-
TURE SENSOR (See page AT±5)
6. REMOVE VALVE BODY
Remove the 21 bolts and valve body.
7. REMOVE CHECK BALL BODY AND SPRING
NOTICE:
Do not drop the check ball body and spring.

D00754
A
CB
B
B
B
C
CA
DB
AT±10
± AUTOMATIC TRANSMISSIONVALVE BODY ASSEMBLY
1958 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
(b) Install the 21 bolts.
Torque: 10 N´m (100 kgf´cm, 7 ft´lbf)
Bolt length:
Bolt A: 23 mm (0.91 in.)
Bolt B: 28 mm (1.10 in.)
Bolt C: 36 mm (1.42 in.)
Bolt D: 55 mm (2.17 in.)
12. INSTALL SOLENOID WIRING WITH ATF TEMPERA-
TURE SENSOR (See page AT±5)
13. INSTALL OIL STRAINER (See page AT±5)
14. INSTALL OIL PAN (See page AT±5)
15. INSTALL DRAIN PLUG WITH NEW GASKET
Torque: 20 N´m (205 kgf´cm, 15 ft´lbf)
16. FILL FLUID AND CHECK FLUID (See page DI±318)

BE0HA±02
I04033
HI
Flash OFFTAIL HEAD AUTO
LO
± BODY ELECTRICALHEADLIGHT AND TAILLIGHT SYSTEM
BE±37
2338 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
INSPECTION
1. FAIL±SAFE FUNCTION
(Light Control ECU)
When input error is inspected.
When input voltage is not within the range of operation voltage (9 to 16 V),
lighting of the headlight stops. As soon as the voltage comes within the range,
it lights up again.
However if the input voltage becomes low after lighting up,
sufficient voltage is maintained until light of bulb completely goes off.
When output error is inspected (Open or short).
When light flushing is inspected.
When an error occurs in the output voltage (open or short) or flushing symptom
occurs on the bulb, lighting of the headlight stops, the condition is maintained
until power is turned ON again (headlight dimmer switch OFF " ON).
In this case, it can not be judged whether lighting malfunction is caused by an
output error or other reasons (fuse blown out, etc.).
Check that there is no error in fuse and wiring (including power source) and
replace the bulb in the first place, when the error still appears, replace the light
control ECU.
2. INSPECT LIGHT CONTROL SWITCH CONTINUITY
Switch positionTester connectionSpecified condition
OFF±No continuity
TAIL15 ± 16Continuity
HEAD14 ± 15 ± 16Continuity
AUTO13 ± 16Continuity
If continuity is not as specified, replace the switch.
3. INSPECT HEADLIGHT DIMMER SWITCH CONTINU-
ITY
Switch positionTester connectionSpecified condition
Low beam17 ± 18Continuity
High beam8 ± 17Continuity
Flash8 ± 9 ± 17Continuity
If continuity is not as specified, replace the switch.

BE0HI±03
I04248
Connector ºUºConnector ºAº Connector ºBº
Combination Meter Wiring Circuit Connectors
Connector ºAº Connector ºBº Connector ºUº BE±82
± BODY ELECTRICALCOMBINATION METER
2383 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
CIRCUIT

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)

I04251

Combination Meter Wiring Circuit ± 2
Left Turn Indicator
Right Turn Indicator
Hi±beam Indicator
SRS Warning
Washer Level Indicator
Headlight leveling
Indicator
Malfunction
Indicator
VSC Warning
ABS Warning
VSC OFF Indicator
SLIP Indicator IG+IG+ IG+
IG+
IG+
IG+Combination Meter ECU
A14 A15 A16 A13 A12 B18 A10 to HEAD FuseB15B3B2
A7
B12Headlight Dimmer Switch
Airbag Sensor Assembly
Washer Fluid Level
Warning Switch
Healight Leveing
Contorl ECU
ECM
ABS, TRAC and
VSC ECU Turn Singal
Flasher RelayODO/TRIP Switch
RESET Switch to Combination Meter ECU
to Combination Meter ECUU8
U3
U10
U9
U4
SRS +B BE±84
± BODY ELECTRICALCOMBINATION METER
2385 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)