2000 LEXUS GS400 lumbar support

BE0GK±06
I01367
Driver Side Junction Block

P SEAT (D) Fuse
Power Seat SwitchLumbar Support SwitchLifter Motor
Front Vertical Motor
Slide Motor
Reclining Motor
Power Seat SwitchLumbar Support Switch
Passenger Side Junction Block

P SEAT (P) Fuse
Lumbar Support Motor
Front Vertical Motor
Lumbar Support Switch
Lifter Motor
BE±166
± BODY ELECTRICALPOWER SEAT CONTROL SYSTEM
2467 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
POWER SEAT CONTROL SYSTEM
LOCATION

I05472
Wire Harness Side
I04161
RELEASE FORWARD
± BODY ELECTRICALPOWER SEAT CONTROL SYSTEM
BE±169
2470 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
Reclining switch:
Switch positionTester connectionSpecified condition
FORWARD1 ± 3
2 ± 4Continuity
OFF2 ± 4
3 ± 4Continuity
REAR1 ± 2
3 ± 4Continuity
If continuity is not as specified, replace the switch.
4. INSPECT PASSENGER'S POWER SEAT SWITCH CIR-
CUIT
(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
4 ± GroundConstantContinuity
1 ± GroundConstantBattery positive voltage
If circuit is not as specified, inspect the circuits connected to oth-
er parts.
5. INSPECT DRIVER'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.

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.

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.

± BODY ELECTRICALTROUBLESHOOTING
BE±13
2314 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
POWER SEAT CONTROL SYSTEM
SymptomSuspect AreaSee page
Both Driver and Passenger Power seats do not operate.
(Door lock does not operate.)1. ALT M±Fuse
2. Wire HarnessBE±21
±
Driver's seat does not operate.
1. P/SEAT (D) Fuse
2. Power Seat Switch (D)
3. Wire HarnessBE±21
BE±167
±
Passenger's seat does not operate.
1. P/SEAT (P) Fuse
2. Power Seat Switch (P)
3. Wire HarnessBE±21
BE±167
±
ºSlide operationº does not operate.
1. Power Seat Switch (D, P)
2. Wire Harness
3. Slide Motor (D, P)BE±167
±
BE±167
ºFront Vertical Operationº does not operate.
1. Power Seat Switch (D, P)
2. Wire Harness
3. Front Vertical Motor (D, P)BE±167
±
BE±167
ºLifter Operationº does not operate.
1. Power Seat Switch (D, P)
2. Wire Harness
3. Lifter Motor (D, P)BE±167
±
BE±167
ºReclining Operationº does not operate.
1. Power Seat Switch (D, P)
2. Wire Harness
3. Reclining Motor (D, P)BE±167
±
BE±167
ºLumbar Support Operationº does not operate.
1. Power Seat Switch (D, P)
2. Wire Harness
3. Lumbar Support Motor (D, P)BE±167
±
BE±167
(D): Driver's Seat
(P): Passenger's Seat
POWER MIRROR CONTROL SYSTEM
This system uses the multiplex communication system, so check diagnosis system of the multiplex commu-
nication system before you proceed with troubleshooting.
w/ Driving Position Memory System:
SymptomSuspect AreaSee page
Both right and left mirrors do not operate.
1. Mirror Switch
2. Wire Harness
3. Body No.2 ECUBE±176
±
DI±820
Only one side of mirror does not operate.
1. Mirror Motor
2. Wire Harness
3. Driver and Passenger Door ECUBE±176
±
DI±856
DI±889
The mirror does not return to the memorized position.
1. Mirror Position Sensor
(Position is not set)
2. Wire Harness
3. Power Seat Control ECU
BE±176
±
DI±683
The memorized position is moved.
1. Mirror Position Sensor
(Position is not set)
2. Wire Harness
BE±176
±