Page 363 of 1111
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.
Page 366 of 1111
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)
Page 367 of 1111
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)
Page 368 of 1111
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)
Page 448 of 1111
CH043±01
B01372
Except Maintenance±Free Battery
B01888
Maintenance±Free BatteryVoltmeter
± CHARGING (2JZ±GE)CHARGING SYSTEM
CH±1
1603 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
CHARGING SYSTEM
ON±VEHICLE INSPECTION
CAUTION:
Check that the battery cables are connected to the
correct terminals.
Disconnect the battery cables when the battery is giv-
en a quick charge.
Do not do tests with a high voltage insulation resis-
tance tester.
Never disconnect the battery while the engine is run-
ning.
1. CHECK BATTERY ELECTROLYTE LEVEL
Check the electrolyte quantity of each cell.
Maintenance±Free Battery:
If under the lower level, replace the battery (or add distilled wa-
ter if possible). Check the charging system.
Except Maintenance±Free Battery:
If under the lower level, add distilled water.
2. Except Maintenance±Free Battery:
CHECK BATTERY SPECIFIC GRAVITY
Check the specific gravity of each cell.
Standard specific gravity: 1.25 ± 1.29 at 20°C (68°F)
If the specific gravity is less than specification, charge the bat-
tery.
3. Maintenance±Free Battery:
CHECK BATTERY POSITIVE VOLTAGE
(a) After having driven the vehicle and in the case that 20
minutes have not passed after having stopped the en-
gine, turn the ignition switch ON and turn on the electrical
system (headlight, blower motor, rear defogger etc.) for
60 seconds to remove the surface charge.
(b) Turn the ignition switch OFF and turn off the electrical sys-
tems.
(c) Measure the battery positive voltage between the nega-
tive (±) and positive (+) terminals of the battery.
Standard voltage: 12.5 ± 12.9 V at 20°C (68°F)
If the voltage is less than specification, charge the battery.
4. CHECK BATTERY TERMINALS AND FUSES
(a) Check that the battery terminals are not loose or cor-
roded.
If the terminals are corroded, clean the terminals.
(b) Check the fusible link and fuses for continuity.
Page 480 of 1111
B01900
CO0AD±03
B00922
ECT
Switch
Connector
B02072
B02073
Ammeter
Battery(+)
(±)
CO±24
± COOLING (2JZ±GE)ELECTRIC COOLING FAN
1562 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
ELECTRIC COOLING FAN
ON±VEHICLE INSPECTION
1. CHECK COOLING FAN OPERATION WITH LOW
TEMPERATURE (Below 83°C (181°F))
(a) Turn the ignition switch ON.
(b) Check that the cooling fan stops.
If not, check the cooling fan relay and ECT switch, and check
for a separated connector or severed wire between the cooling
fan relay and ECT switch.
(c) Disconnect the ECT switch connector.
(d) Check that the cooling fan rotates.
If not, check the fuses, radiator fan main relay, cooling fan relay,
cooling fan, and check for a short circuit between the cooling
fan relay and ECT switch.
(e) Reconnect the ECT switch connector.
2. CHECK COOLING FAN OPERATION WITH HIGH
TEMPERATURE (Above 93°C (199°F))
(a) Start the engine, and raise coolant temperature to above
93°C (199°F).
HINT:
Coolant temperature is the detected value by the ECT switch
on the radiator lower tank.
(b) Check that the cooling fan rotates.
If not, replace the ECT switch.
3. INSPECT COOLING FANS
(a) Disconnect the cooling fan connector.
(b) Connect battery and ammeter to the cooling fan connec-
tor.
(c) Check that the cooling fan rotates smoothly, and check
the reading on the ammeter.
Standard amperage: 8.5 ± 11.5 A at 20°C (68°F)
(d) Reconnect the cooling fan connector.
Page 641 of 1111
IN±38
± INTRODUCTIONTERMS
38 Author: Date:
2000 LEXUS GS300/GS400 (RM718U) H±FUSE
High Current Fuse
HIHigh
HIDHigh Intensity Discharge (Head Lamp)
HSGHousing
HTHard Top
HWSHeated Windshield System
IACIdle Air Control
ICIntegrated circuit
IDIIndirect Diesel Injection
IFSIndependent Front Suspension
IGIgnition
IIAIntegrated Ignition Assembly
INIntake (Manifold, Valve)
INTIntermittent
I/PInstrument Panel
IRSIndependent Rear Suspension
J/BJunction Block
J/CJunction Connector
KDKick±Down
LANLocal Area Network
LBLiftback
LCDLiquid Crystal Display
LEDLight Emitting Diode
LHLeft±Hand
LHDLeft±Hand Drive
L/H/WLength, Height, Width
LLCLong±Life Coolant
LNGLiquified Natural Gas
LOLow
LPGLiquified Petroleum Gas
LSDLimited Slip Differential
LSP & PVLoad Sensing Proportioning And Bypass Valve
LSPVLoad Sensing Proportioning Valve
MAX.Maximum
MICMicrophone
MILMalfunction Indicator Lamp
MIN.Minimum
MPMultipurpose
MPXMultiplex Communication System
M/TManual Transmission
MTMount
MTGMounting
NNeutral
NANatural Aspiration
No.Number
O/DOverdrive
Page 645 of 1111
BE1367
Medium Current Fuse and High Current Fuse
Equal Amperage Rating
V00076
Abbreviation Part Name Symbol Illustration
FUSE
MEDIUM CURRENT FUSE
HIGH CURRENT FUSE
FUSIBLE LINK
CIRCUIT BREAKERFUSE
M±FUSE
H±FUSE
FL
CB
± INTRODUCTIONREPAIR INSTRUCTIONS
IN±5
5 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
(3) Precoated parts are indicated in the component il-
lustrations by the ºº symbol.
(g) When necessary, use a sealer on gaskets to prevent
leaks.
(h) Carefully observe all specifications for bolt tightening
torques. Always use a torque wrench.
(i) Use of special service tools (SST) and special service ma-
terials (SSM) may be required, depending on the nature
of the repair. Be sure to use SST and SSM where speci-
fied and follow the proper work procedure. A list of SST
and SSM can be found in Preparation section in this
manual.
(j) When replacing fuses, be sure the new fuse has the cor-
rect amperage rating. DO NOT exceed the rating or use
one with a lower rating.
