2000 LEXUS GS400 warning lights

BE0GR±04
I04055
2 5
I04146
I04147
Not turned
UNLOCK
I04148
ON OFF BE±150
± BODY ELECTRICALTHEFT DETERRENT SYSTEM
2451 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
INSPECTION
1. INSPECT THEFT DETERRENT INDICATOR LIGHT OP-
ERATION
Connect the positive (+) lead from the battery terminal 2 and
negative (±) lead to terminal 5, and check that the warning light
lights up.
If operation is not as specified, replace the light control rheostat.
2. INSPECT THEFT DETERRENT INDICATOR LIGHT
CIRCUIT
(See page DI±808)
3. INSPECT THEFT DETERRENT HORN OPERATION
Connect the positive (+) lead from the battery to the terminal 1
and negative (±) lead to theft deterrent horn body, and check
that the theft deterrent horn blows.
If operation is not as specified, replace the horn.
4. INSPECT THEFT DETERRENT HORN CIRCUIT
(See page DI±804)
5. INSPECT LUGGAGE COMPARTMENT DOOR KEY
LOCK AND UNLOCK SWITCH CONTINUITY
Switch positionTester connectionSpecified condition
Not turned±No continuity
UNLOCK1 ± 2Continuity
If continuity is not as specified, replace the switch.
6. INSPECT LUGGAGE COMPARTMENT DOOR KEY
LOCK AND UNLOCK SWITCH CIRCUIT
(See page DI±794)
7. INSPECT ENGINE HOOD COURTESY SWITCH CON-
TINUITY
Switch positionTester connectionSpecified condition
LOCK±No continuity
UNLOCK1 ± 2Continuity
If continuity is not as specified, replace the switch.
8. INSPECT ENGINE HOOD COURTESY SWITCH CIR-
CUIT
(See page DI±790)

BE0GN±01
BE±152
± BODY ELECTRICALWIRELESS DOOR LOCK CONTROL SYSTEM
2453 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
PRE±CHECK
Make the vehicle in the initialized condition:
The initialized condition is the condition when the following conditions are satisfied.
(1) Key plate has not been inserted in the ignition key cylinder.
(2) All the doors are closed. (Door warning light is OFF.)
(3) All the doors are locked.
(4) Wireless door lock control switch (Buzzer switch) is ON.
Under the standard operation, when repeating UNLOCK and LOCK switch 3 times or more alternately, check the
UNLOCK±LOCK operation from 3rd time onward.

Following procedures are standard operation.
(1) Keep about 1 M away to the right direction from the outside handle of a driver's seat.
(2) Face the transmitter toward the vehicle and press one of transmitter switches for about 1 sec.


As of the security function, even the wireless function is normal, there may be the case that only UNLOCK opera-
tion will not work.

As of the body customize function, if ºoperation twiceº has been set using LEXUS hand±held tester, only driver's
seat is unlocked by unlock operation performed once.
Normal


Operative distance may differ according to
an operator, the way of holding the transmitter
or position.

Because weak electric wave is used, when
there is strong wave or noise in the used
frequency ,operation distance might be
shortened.
No Yes
Only wireless function (Remote control) will not operate.
(If a new transmitter or a transmitter of the same type that works properly with the vehicle is not available.)
Check when pressing UNLOCK switch
and LOCK switch under standard
operation, that the transmitter LED
lights up once more.
NoYe s
Basic function check:
Transmitter LED inspection:

BE±6
± BODY ELECTRICALTROUBLESHOOTING
2307 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
HEADLIGHT BEAM LEVEL CONTROL SYSTEM
SymptomSuspect AreaSee page
Beam axis is not controlled. (It is not initialized.)
Headlight Beam Level Control System does not operate.
1. ECU±IG Fuse
2. Headight Beam Level Control Actuator
3. Headlight Beam Level Control ECU
4. Wire Harness SideBE±21
BE±50
BE±50
±
Beam axis is not controlled. (It is initialized.)
Headlight Beam Level Control System does not operate.1. Height Control Sensor
2. Headlight Beam Level Control ECU
3. Wire Harness SideBE±50
BE±50
±
Controlled angle of head light is unusual.
(The angle is controlled.)
1. Height Control Sensor
2. Headlight Beam Level Control ECU
3. Headlights
4. Wire Harness Side±
BE±50
BE±3
±
Beam axis position is not stable during driving.
1. ABS System
2. Headlights
3. Wire HarnessDI±387
BE±3
±
FOG LIGHT SYSTEM
This system uses the multiplex communication system, so check diagnosis system of the multiplex commu-
nication system before you proceed with troubleshooting.
SymptomSuspect AreaSee page
Fog light does not light up with light control SW HEAD
(Headlight is normal.)
1. FOG Fuse
2. Fog Light Relay
3. Fog Light Switch
4. Wire Harness
5. Body No.2 ECUBE±21
BE±53
BE±53
±
±
Fog light does not light up with light control SW HEAD
(Headlight does not light).1.*1 Other Parts
2. Wire Harness±
±
Only one light does not light up.1. Bulb
2. Wire Harness±
±
*1: Inspect Headlight System
TURN SIGNAL AND HAZARD WARNING SYSTEM
This system uses the multiplex communication system, so check diagnosis system of the multiplex commu-
nication system before you proceed with troubleshooting.
SymptomSuspect AreaSee page
ºHazardº and ºTurnº do not light up.
1. GAUGE Fuse
2. TURN HAZ Fuse
3. Ignitioin Switch
4. Turn Signal Flasher Relay
5. Wire HarnessBE±21
BE±21
BE±31
BE±56
±
Hazard warning light does not light up.
(Turn is normal)1. Hazard Warning Switch
2. Wire HarnessBE±56
±
Turn signal does not light up.
(Hazard is normal)1. Turn Signal Switch
2. Wire HarnessBE±56
±
Turn signal does not light up in one direction.1. Turn Signal Switch
2. Wire HarnessBE±56
±
Only one bulb does not light up.1. Bulb
2. Wire Harness±
±

I04265
I01663
1 2 OFF
ON
3 4
I04032
Wire Harness Side BE±32
± BODY ELECTRICALIGNITION SWITCH AND KEY UNLOCK WARNING
SWITCH
2333 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
3. INSPECT IGNITION KEY ILLUMINATION OPERATION
Connect the positive (+) lead from the battery to terminal 1 and
the negative (±) lead to terminal 2, and check that the indicator
light lights up.
If operation is not as specified, replace the switch.
4. INSPECT IGNITION KEY ILLUMINATION CIRCUIT
(See page DI±843)
5. INSPECT KEY UNLOCK WARNING SWITCH CONTI-
NUITY
Switch positionTester connectionSpecified condition
OFF (Key removed)±No continuity
ON (Key set)1 ± 2Continuity
If continuity is not as specified, replace the switch.
6. INSPECT KEY UNLOCK WARNING SWITCH CIRCUIT
(See page DI±828)
Connect the switch connector and inspect the connector on
wire harness side from the back side, as shown.
Tester connectionConditionSpecified condition
1 ± GroundConstantContinuity
If circuit is not as specified, inspect the circuits connected to oth-
er parts.

BE0H0±06
I01353
Turn Signal LightsEngine Room No.1
Junction Block

TURN HAZ Fuse
Ignition Switch
Combination Switch

Turn Signal Switch
Hazard Warning Switch
Turn Signal Lights Turn Signal Lights
Driver Side Junction Block

GAUGE FuseCowl Side No.5
Junction Block

Turn Signal Flaher
± BODY ELECTRICALTURN SIGNAL AND HAZARD WARNING SYSTEM
BE±55
2356 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
TURN SIGNAL AND HAZARD WARNING SYSTEM
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)

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

I04091
F
E1
2
1/2
I04094
A
D
C
B
I01277
Battery Ignition
SwitchWarning Light
Wire Harness Side
1 BE±98
± BODY ELECTRICALCOMBINATION METER
2399 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
13. INSPECT FUEL SUB SENDER GAUGE RESISTANCE
Measure the resistance between terminals 1 and 2 for each
float position.
Float position mm (in.)Resistance (W)
F: Approx. 9.5 (0.37) ± 3 (0.12)Approx. 2.0 ± 1.0
1/2: Approx. 110.5 (4.35) ± 3 (0.12)Approx. 33.0 ± 3.0
E: Approx. 206.5 (8.13) ± 3 (0.12)Approx. 61.3 ± 1.0
If resistance value is not as specified, replace the sub sender
gauge.
14. INSPECT ENGINE COOLANT TEMPERATURE RE-
CEIVER GAUGE OPERATION (See page DI±754)
15. INSPECT ENGINE COOLANT TEMPERATURE RE-
CEIVER GAUGE RESISTANCE
Measure the resistance between terminals with fixing pointer to
the stopper.
Tester connectionResistance (W)
A ± B140 ± 185
C ± D130 ± 175
If resistance value is not as specified, replace the receiver
gauge.
HINT:
This circuit includes the diode.
If resistance value is not as specified, replace the receiver
gauge.
16. INSPECT LOW OIL PRESSURE WARNING LIGHT
(a) Disconnect the connector from the warning 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, test the bulb.