2000 LEXUS GS400 Service Repair Manual

I04162
Wire Harness Side
I04161
RELEASE FORWARD
I04162
Wire Harness Side BE±170
± BODY ELECTRICALPOWER SEAT CONTROL SYSTEM
2471 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
6. INSPECT DRIVER'S LUMBAR SUPPORT SWITCH
CIRCUIT
(a) Disconnect the switch connector and connect the seat
wire harness to the floor wire harness.
(b) Inspect the connector on the wire harness side.
Tester connectionConditionSpecified condition
3 ± GroundConstantContinuity
4 ± GroundConstantBattery positive voltage
If circuit is not as specified, inspect the circuits connected to oth-
er parts.
7. INSPECT PASSENGER'S LUMBAR SUPPORT
SWITCH CONTINUITY
Switch positionTester connectionSpecified condition
FORWARD1 ± 4
2 ± 3Continuity
OFF1 ± 3
2 ± 3Continuity
RELEASE1 ± 3
2 ± 4Continuity
If continuity is not as specified, replace the switch.
8. INSPECT PASSENGER'S LUMBAR SUPPORT
SWITCH CIRCUIT
(a) Disconnect the switch connector and connect the seat
wire harness to the floor wire harness.
(b) Inspect the connector on the wire harness side.
Tester connectionConditionSpecified condition
2 ± GroundConstantContinuity
1 ± GroundConstantBattery positive voltage
If circuit is not as specified, inspect the circuits connected to oth-
er parts.

N21865
(a)
(b)
2
112
N21866
21
N21867
2
1
N21865
(a)
(b)
21
1
2
N22086
21
± BODY ELECTRICALPOWER SEAT CONTROL SYSTEM
BE±171
2472 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
9. INSPECT SLIDE MOTOR OPERATION
(a) Connect the positive (+) lead from the battery to terminal
1 and the negative (±) lead to terminal 2, check that the
motor turns counterclockwise.
(b) Reverse the polarity, check that the motor turns clock-
wise.
If operation is not as specified, replace the seat adjuster.
10. INSPECT SLIDE MOTOR PTC THERMISTOR OPERA-
TION
( ): Passenger side
(a) Connect the positive (+) lead from the battery to terminal
1 (2), the positive (+) lead from the ammeter to terminal
2 (1) and the negative (±) lead to the battery negative (±)
terminal, then move the seat cushion to the front position.
(b) Continue to apply voltage, check that current changes to
less than 1 ampere within 4 to 90 seconds.
(c) Disconnect the leads from terminals.
(d) Approximately 60 seconds later, connect the positive (+)
lead from the battery to terminal 2 (1) and the negative (±)
lead to terminal 1 (2), check that the seat cushion begins
to move backwards.
If operation is not as specified, replace the seat adjuster.
11. INSPECT FRONT VERTICAL MOTOR OPERATION
(a) Connect the positive (+) lead from the battery to terminal
1 and the negative (±) lead to terminal 2, check that the
motor turns counterclockwise.
(b) Reverse the polarity, check that the motor turns clock-
wise.
If operation is not as specified, replace the seat adjuster.
12. INSPECT FRONT VERTICAL MOTOR PTC THERM-
ISTOR OPERATION
( ): Passenger side
(a) Connect the positive (+) lead from the battery to terminal
1 (2), the positive (+) lead from the ammeter to terminal
2 (1) and the negative (±) lead to the battery negative (±)
terminal, then move the seat cushion to the highest posi-
tion.
(b) Continue to apply voltage, check that the current changes
to less than 1 ampere within 4 to 90 seconds.

N22087
21
N21865
(a)
1(b)
2
2
1
N22088
21
N22089
21
N21865
(a)
(b)
2
1
1 2 BE±172
± BODY ELECTRICALPOWER SEAT CONTROL SYSTEM
2473 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
(c) Disconnect the leads from the terminals.
(d) Approximately 60 seconds later, connect the positive (+)
lead from the battery to terminal 2 (1) and the negative (±)
lead to terminal 1 (2), check that the seat cushion begins
to descend.
If operation is not as specified, replace the seat adjuster.
13. INSPECT LIFTER MOTOR OPERATION
(a) Connect the positive (+) lead from the battery to terminal
1 and the negative (±) lead to terminal 2, check that the
motor turns counterclockwise.
(b) Reverse the polarity, check that the motor turns clock-
wise.
If operation is not as specified, replace the seat adjuster.
14. INSPECT LIFTER MOTOR PTC THERMISTOR OPERA-
TION
(a) Connect the positive (+) lead from the battery to terminal
2 (1), the positive (+) lead from the ammeter to terminal
1 (2) and the negative (±) lead to the battery negative (±)
terminal, then move the seat cushion to the highest posi-
tion.
(b) Continue to apply voltage, check that the current changes
to less than 1 ampere within 4 to 90 seconds.
(c) Disconnect the leads from the terminals.
(d) Approximately 60 seconds later, connect the positive (+)
lead from the battery to terminal 1 (2) and the negative (±)
lead to terminal 2 (1), check that the seat cushion begins
to descend.
If operation is not as specified, replace the seat adjuster.
15. INSPECT RECLINING MOTOR OPERATION
(a) Connect the positive (+) lead from the battery to terminal
1 and the negative (±) lead to terminal 2, check that the
motor turns counterclockwise.
(b) Reverse the polarity, check that the motor turns clock-
wise.
If operation is not as specified, replace the seat adjuster.

N21868
21
N21869
21
I04163
1 2
I05473
1 2
I04165
21
± BODY ELECTRICALPOWER SEAT CONTROL SYSTEM
BE±173
2474 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
16. INSPECT RECLINING MOTOR PTC THERMISTOR OP-
ERATION
(a) Connect the positive (+) lead from the battery to terminal
2, the positive (+) lead from the ammeter to terminal 1 and
the negative (±) lead to the battery negative (±) terminal,
then recline the seat back to the most forward position.
(b) Continue to apply voltage, check that the current changes
to less than 1 ampere within 4 to 90 seconds.
(c) Disconnect the leads from the terminals.
(d) Approximately 60 seconds later, connect the positive (+)
lead from the battery to terminal 1 and the negative (±)
lead to terminal 2, check that the seat back begins to fall
backward.
If operation is not as specified, replace the seat adjuster.
17. INSPECT LUMBAR SUPPORT MOTOR OPERATION
(a) Connect the positive (+) lead from the battery to terminal
1 and the negative (±) lead to terminal 2, check that the
lumbar support moves to release side.
(b) Reverse the polarity, check that the lumbar support
moves forward.
If operation is not as specified, replace the seat adjuster.
18. INSPECT LUMBAR SUPPORT MOTOR CIRCUIT
BREAKER OPERATION
(a) Connect the positive (+) lead from the battery to terminal
2 and the negative (±) lead to terminal 1 on the lumbar
support motor connector and move the lumbar support to
front end position.

I04166
21
BE±174
± BODY ELECTRICALPOWER SEAT CONTROL SYSTEM
2475 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
(b) Continue to apply voltage, check that a circuit breaker op-
eration noise can be heard within 4 to 60 seconds.
(c) Reverse the polarity, check that the lumbar support be-
gins to move release side with in spproximately 60 se-
conds.
If operation is not as specified, replace the motor.

BE02J±10
I01368
Mirror Assembly

Mirror Motor
Mirror Switch

Left/Right Adjustment Switch

Mirror Control SwitchIgnition Switch
Driver Side Junction Block

Body ECU No.2
± BODY ELECTRICALPOWER MIRROR CONTROL SYSTEM
BE±175
2476 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
POWER MIRROR CONTROL SYSTEM
LOCATION

BE10W±02
I04167
Left/Right Adjustment Switch
Mirror Switch
9
7
6
5 8
I07733
Retract Switch
Mirror Switch
Left/Right
Adjustment Switch
Mirror Switch
Retract Switch 9
8
7
6
5
BE±176
± BODY ELECTRICALPOWER MIRROR CONTROL SYSTEM
2477 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
INSPECTION
1. USA/CANADA models:
INSPECT MIRROR SWITCH CONTINUITY
Switch positionTester connectionResistance (W)
LEFT8 ± 9100
RIGHT8 ± 90
Illumination5 ± 6Continuity
Measure resistance between terminals 7 and 9.
Switch positionResistance (W)
UPApprox. 100
RIGHT250
DOWN470
LEFT800
If continuity is not as specified, replace the switch.
2. USA/CANADA models:
INSPECT MIRROR SWITCH CIRCUIT
(See page DI±837)
3. TAIWAN model:
INSPECT MIRROR SWITCH CONTINUITY
Switch positionTester connectionResistance (W)
LEFT8 ± 9100
RIGHT8 ± 90
Illumination5 ± 6Continuity
Measure resistance between terminals 7 and 9.
Switch positionResistance (W)
UPApprox. 100
RIGHT250
DOWN470
LEFT800
If continuity is not as specified, replace the switch.
4. TAIWAN model:
INSPECT RETRACT SWITCH CONTINUITY
Switch positionTester connectionSpecified condition
OFF±No continuity
ON1 ± 2Continuity
If continuity is not as specified, replace the switch.
5. TAIWAN model:
INSPECT MIRROR SWITCH CIRCUIT
(See page DI±837)

I04270
5 4
I04271
5 4
I04272
56
I04273
56
I04168
12
± BODY ELECTRICALPOWER MIRROR CONTROL SYSTEM
BE±177
2478 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
6. w/o Driving position memory:
INSPECT MIRROR MOTOR OPERATION
(a) Connect the positive (+) lead from the battery to terminal
4 and the negative (±) lead to terminal 5, and check that
the mirror turns to the left side.
(b) Reverse the polarity, and check that the mirror turns to the
right side.
(c) Connect the positive (+) lead from the battery to terminal
6 and the negative (±) lead to terminal 5, and check that
the mirror turns upward.
(d) Reverse the polarity, and check that the mirror turns
downward.
If operation is not as specified, replace the mirror assembly.
7. w/o Driving position memory:
INSPECT MIRROR MOTOR CIRCUIT
Left side: (See page DI±882)
Right side: (See page DI±916)
8. w/ Driving position memory:
INSPECT MIRROR MOTOR OPERATION
(a) Connect the positive (+) lead from the battery to terminal
1 and the negative (±) lead to terminal 2, and check that
the mirror turns to the left side.