2000 LEXUS GS400 ignition

AC0Y2±01
I03743
1 2 AC±80
± AIR CONDITIONINGCONDENSER FAN
2765 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
CONDENSER FAN
ON±VEHICLE INSPECTION
1. INSPECT CONDENSER FAN OPERATION
Inspect the fan operation, as shown in the chart below.
Test conditions:

Ignition switch ON

Blower speed control switch position ºHIº

Temperature control dial at ºMAX. COOLº

Install manifold gauge setº

A/C switch ON
ConditionFan operation (Fan speed)
Engine coolant temperature
91°C (196 °F) or belowRotate (Low speed)
Engine coolant temperature
100°C (212 °F) or aboveRotate (High speed)
Refrigerant pressure is less than
1,520 kPa (15.5 kgf´cm2, 220 psi)Rotate (Low speed)
Refrigerant pressure is 1,520 kPa
(15.5 kgf´cm2, 220 psi) or aboveRotate (High speed)
If operation is not as specified, proceed to the next inspection.
2. INSPECT CONDENSER FAN MOTOR OPERATION
(a) Disconnect the fan connector.
(b) Connect the positive (+) lead from the battery to terminal
2 and negative (±) lead to terminal 1 then check that motor
operations smoothly.

If operation is not as specified, replace the fan mo-
tor.

If operation is as specified, check the pressure
switch, cooling fan relays and engine coolant temp.
switch.

AT066±01
AT±26
± AUTOMATIC TRANSMISSIONFLOOR SHIFT ASSEMBLY
1974 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
INSTALLATION
Installation is in the reverse order of removal.
(See page AT±16)
HINT:
After installation, inspect the shift lever position.

When shifting from P to R position only with ignition switch ON and brake pedal, make sure that the
shifting lever moves smoothly and can be moderately operated.

When starting engine, make sure that the vehicle moves forward when shifting from N to D position
and moves rearward when shifting to R position.

BE0GU±05
I01361
Ignition Switch
Buckle Switch
Driver Side Junction Block

ECU±IG Fuse
Electric Tension Reducer Solenoid
BE±104
± BODY ELECTRICALELECTRIC TENSION REDUCER SYSTEM
2405 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
ELECTRIC TENSION REDUCER SYSTEM
LOCATION

BE0GV±04
I04110
(b) (d)
Slowly
RetractedRetracted
More Quickly
I04111
Wire Harness Side
± BODY ELECTRICALELECTRIC TENSION REDUCER SYSTEM
BE±105
2406 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
INSPECTION
1. INSPECT TENSION REDUCER SOLENOID OPERA-
TION
(a) Connect the positive (+) lead from the battery to terminal
1, and negative (±) lead to terminal 2.
(b) Pull the belt upward and check that the belt is slowly re-
tracted when released.
(c) Disconnect the lead from the battery.
(d) Pull the belt upward and check that the belt is retracted
more quickly when released than in (b).
HINT:
Do not tilt the retractor.
If the operation is not as specified, replace the front seat outer
belt assembly.
2. INSPECT TENSION REDUCER SOLENOID CIRCUIT
Disconnect the tension reducer solenoid connector and inspect
the connector on wire harness side, as shown.
Tester connectionConditionSpecified condition
2 ± GroundBuckle switch position
OFF (belt unfastened)No continuity
2 ± GroundBuckle switch position
ON (belt fastened)Continuity
1 ± GroundIgnition switch ACC or LOCKNo voltage
1 ± GroundIgnition switch ONBattery positive voltage
If the circuit is specified, replace the front seat outer belt assem-
bly.
If the circuit is not as specified, inspect the circuits connected
to other parts.

BE0GS±10
I01362
Defogger WireIgnition SwitchDefogger Switch
Defogger Switch
Mirror Assembly

Mirror Defogger
LEXUS navigation
System
Passenger Side
Junction Block

DEF M±Fuse

MIR HTR Fuse

Mirror Defogger Relay
Mirror Assembly

Mirror Defogger
Passenger Cowl Side
Relay Block

Defogger Relay
± BODY ELECTRICALDEFOGGER SYSTEM
BE±107
2408 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
DEFOGGER SYSTEM
LOCATION

BE0GT±03
I04112
6
I04113
I04114
Wire Harness Side
Connector ºAº Connector ºBº
I01200
2 1
35
2 5
1 3
BE±108
± BODY ELECTRICALDEFOGGER SYSTEM
2409 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
INSPECTION
1. INSPECT DEFOGGER TIMER OPERATION
(a) Connect the positive (+) lead from the voltmeter to termi-
nal 6 of body ECU No.1 connector and negative (±) lead
to body ground.
(b) When the switch is OFF, the voltage should be approx.
12V.
(c) Turn the defogger switch ON and check that the indicator
lights up and that the voltage is less than 1 V.
(d) After 15 minutes, check that the switch is OFF and the
voltage is approx. 12 V.
If operation is not as specified, replace the switch.
2. INSPECT DEFOGGER SWITCH (in PANEL SWITCH)
CIRCUIT
Connector disconnected:
Disconnect the connector from the panel switch and inspect the
connector on wire harness side, as shown in the chart.
Tester connectionConditionSpecified condition
B10 ± GroundConstantContinuity
A1 ± GroundConstantBattery voltage
A2 ± GroundIgnition switch LOCKNo voltage
A2 ± GroundIgnition switch ACC or ONBattery voltage
If the circuit is not as specified, replace the switch.
3. INSPECT DEFOGGER 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.
4. INSPECT DEFOGGER RELAY CIRCUIT
(See page DI±812 and BE±21)

I01200
2 1
35
2 5
1 3
I01291
Tester Probe
Tin FoilHeat Wire
I01292
At Center
I01293
0 Volts
Broken
WireSeveral
Volts
Battery
side Ground sideFoil strip


± BODY ELECTRICALDEFOGGER SYSTEM
BE±109
2410 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
5. INSPECT MIRROR DEFOGGER 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.
6. INSPECT MIRROR DEFOGGER RELAY CIRCUIT
(See page BE±21)
7. INSPECT DEFOGGER WIRE
NOTICE:

When cleaning the glass, use a soft, dry cloth, and wipe the
glass in the direction of the wire. Take care not to damage
the wires.

Do not use detergents or glass cleaners with abrasive in-
gredients.

When measuring voltage, wrap a piece of tin foil around the
tip of the negative probe and press the foil against the wire
with your finger, as shown.
(a) Turn the ignition switch ON.
(b) Turn the defogger switch ON.
(c) Inspect the voltage at the center of each heat wire, as
shown.
VoltageCriteria
Approx. 5VOkay (No break in wire)
Approx. 10V or 0VBroken wire
HINT:
If there is approximately 10 V, the wire is broken between the
center of the wire and the positive (+) end. If there is no voltage,
the wire is broken between the center of the wire and ground.
(d) Place the voltmeter positive (+) lead against the defogger
wire on the battery side.
(e) Place the voltmeter negative (±) lead with the foil strip
against the wire on the ground side.
(f) Slide the positive (+) lead from battery to ground side.
(g) The point where the voltmeter deflects from several V to
zero V is the place where the defogger wire is broken.
HINT:
If the heat wire is not broken, the voltmeter indicates 0 V at the
positive (+) end of the heat wire but gradually increases to about
12 V as the meter probe moves to the other end.

Only specific window does not operate. (Neither manual nor automatic operation is available.)1
Diagnosis check:
Check output diagnosis trouble codes 21 ± 26 when operating the
master switch and power window switch.
(Refer to ºMultiplex Communication Systemº)If the door lock of the applicable seat operates.
Wire harness faulty or
D FR DOOR fuse faulty.
No Yes
Disconnect the driver door control ECU connector.
Ye sNo
Voltage check:
With ignition switch ON if 10 to 14 V power is
supplied to PCT (3) of power window switch.Wire harness faulty.
(Between master switch W/L2 terminal
(10) and power window switch PCT
terminal (3)
Continuity check:
Master switch faulty.
Check continuity master switch and power window switch.No (Driver side)
No (Except driver side)Ye s
No Ye s
Wire harness check:
Master switch
Master switch Driver door control ECU
AUTO (7)
DDN (18)
DUP (6)AUTO (B6)
MDN (B4)
MUP (B5)
Power window switch
Power window switch Driver door control ECU
A (5)
D (4)
U (6)AUTO (A22)
MDN (A23)
MUP (A24)
Wire harness faulty.
Continuity check:
Check continuity between UP terminal (A2) and
GND terminal (C12), DN terminal (A11) and
GND terminal (C12) of driver door control ECU .
Ye s
When replacing with the normal driver door control ECU
removed from another seat, if it operates normally.
Driver door control ECU faulty.No Yes
Driver door control ECU faulty.
No
Power window motor check:
Disconnect the motor connector.
Connect the battery positive (+) lead to terminal
UP (2) and negative (±) lead to terminal DN
(1) of wire harness side motor connector, check that
the motor operates.
Check power window motor.Ye s
No
Wire harness faulty.
Ye s
Power window motor faulty.
No
BE±112
± BODY ELECTRICALPOWER WINDOW CONTROL SYSTEM
2413 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
FLOW CHART