LEXUS GS400 2000 Service Repair Manual

BE±162
± BODY ELECTRICALWIRELESS DOOR LOCK CONTROL SYSTEM
2463 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
2. REPLACE DOOR CONTROL RECEIVER AND TRANS-
MITTER
NOTICE:
When replacing the door control receiver and transmitter,
registration of recongnition code is necessary because
they are provided as single components.
(a) Select which operation mode should be performed from
the following modes.
Add mode
Rewrite mode
Prohibition mode
Confirmation mode
HINT:
The add mode is used to retain codes already registered
while you register new recongnition codes. This mode is
used when adding a transmitter. However, if the number
of registered codes exceeds 4 codes, previously regis-
tered codes are correspondingly erased in order, starting
from the first registered code.
The rewrite mode is used to erase all previously regis-
tered codes and register only new recognition codes.
The prohibition mode is used to erase all registered codes
and cancels the wireless door lock function. Use this
mode when the transmitter is lost.
The confirmation mode is for confirming how many re-
congnition codes are already registered before you regis-
ter additional recognition codes.
(b) Follow the chart on the following pages to register the
transmitter recongnition code at the wireless door lock
conrol receiver.
HINT:
When procedure is out of the specified, the operation re-
turns to normal operation.
Maximum 4 recognition codes can be registered.

± BODY ELECTRICALWIRELESS DOOR LOCK CONTROL SYSTEM
BE±163
2464 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
Start registration of recognition code
The vehicle should be in the following conditions.

Any door is OPEN. (Other doors are CLOSED)

Any door is UNLOCKED.

Insert the key into the ignition key cylinder, then pull it out.
Press the door lock control switch (for manual operation) 5 times to
LOCK/UNLOCK at approx. 1 sec. interval.
1st time 2nd time 3rd time 4th time 5th time
LOCK
OFF
UNLOCK
Approx.
1 sec.Approx.
1 sec.
Close the all door, then open the any door.
Again press the door lock control switch (for manual operation) 5 times to
LOCK/UNLOCK at approx. 1 sec. interval.
1st time 2nd time 3rd time 4th time 5th time
LOCK
OFF
UNLOCK
Approx.
1 sec.Approx.
1 sec.
Insert the key into the ignition key cylinder.
Within
40 secs.
Within
40 secs.

BE±164
± BODY ELECTRICALWIRELESS DOOR LOCK CONTROL SYSTEM
2465 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
Within
3 secs.
Turn the ignition switch from ON to LOCK at approx. 1 sec. interval 1 to 5 times to select the mode.
Pull out the key plate from the ignition key cylinder.
When add mode or rewrite mode
is selected.When confirmation
mode is selected.
ON
ONON
LOCK
LOCKLOCK
Approx.
1 sec.Approx.
1 sec. Approx. 1 sec.Approx.
1 sec.Approx.
1 sec.
Add mode
Rewrite modeConfirmation mode
ON ± LOCK change occurs 1 time
ON ± LOCK change occurs 2 timesON ± LOCK change occurs 3 times
MPX body ECU automatically performs
the LOCK±UNLOCK operation once
or twice at 1 sec. interval to iniform the
operator that either the add mode or
rewrite mode has been selected.
LOCK±UNLOCK occurs once
LOCK±UNLOCK occurs twice
Indicates that add mode has been selected.
Indicates that rewrite mode has been
selected.
1 sec.
LOCK
1 sec.1 sec.
LOCK
UNLOCK
UNLOCK
LOCK
2 secs.2 secs.
UNLOCK MPX body ECU automatically performs the
LOCK±UNLOCK operation 1 to 4 times at
2 sec. interval to inform the operator of
the number of the registered codes.
HINT:
When the number of the registered code
is 0, the operation is automatically
performed 5 times.
Example:
When the operation is performed twice, it
directs that 2 types of recognition code
have been registered.
1st time 2nd time
Registration of recognition code (Confirmation
mode and prohibition mode) is completed.
ON
LOCK
Approx.
1 sec.Approx.
1 sec.
Prohibition mode
ON ± LOCK change occurs 5 times
When prohibition
mode is selected.

± BODY ELECTRICALWIRELESS DOOR LOCK CONTROL SYSTEM
BE±165
2466 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
MPX body performs LOCK±UNLOCK operation 5 times at a 1 sec.
interval to inform the operator that prohibition mode has been selected.
Press again either one of 3 switches on the transmitter for more than 1 sec.
MPX body ECU automatically performs LOCK±UNLOCK operation once or
twice at a 1 sec. interval to inform the operator that the receiver has received the
signal from the transmitter.
LOCK±UNLOCK occurs once
LOCK±UNLOCK occurs twice Registration of recognition code is completed
Registration of recognition code has not been completed.

Recognition code received first time and second time did not match.
Proceed to continue registration
If even one of the following conditions is satisfied, registration of recognition
codes is completed.

40 secs. elapses since the MPX body ECU response.

The driver's door is closed.

The key plate is inserted in the ignition key cylinder.

4 type recognition codes are registration at one time.
Registration of recognition codes (add mode or rewrite mode) is completed.
Within
3 secs.Within
40 secs.
ON
LOCK
Approx.
1 sec.Approx.
1 sec.
When prohibition
mode is selected.
Press the lock and unlock switches on the transmitter simultaneously within 1 sec.
If LOCK±UNLOCK operation can not be performed at all, the mode returns to the
normal mode, then start with ºStart registration of recognition codeº.
Proceed to finish registration
Within 40 secs.

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

BE0GL±03
I04159
Lifter
Up
DownReclining
Front Vertical
Up
Down FrontBack Forward
Rear
± BODY ELECTRICALPOWER SEAT CONTROL SYSTEM
BE±167
2468 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
INSPECTION
1. INSPECT DRIVER'S POWER SEAT SWITCH CONTI-
NUITY
Slide switch:
Switch positionTester connectionSpecified condition
FRONT1 ± 9
4 ± 6Continuity
OFF4 ± 6
4 ± 9Continuity
BACK1 ± 6
4 ± 9Continuity
Front vertical switch:
Switch positionTester connectionSpecified condition
UP1 ± 10
4 ± 5Continuity
OFF4 ± 5
4 ± 10Continuity
DOWN1 ± 5
4 ± 10Continuity
Lifter switch:
Switch positionTester connectionSpecified condition
UP1 ± 7
4 ± 8Continuity
OFF4 ± 7
4 ± 8Continuity
DOWN1 ± 8
4 ± 7Continuity
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.

I05472
Wire Harness Side
I04160
Lifter
Up
Down Reclining
Front Vertical
Up
DownFront Back Forward
Rear BE±168
± BODY ELECTRICALPOWER SEAT CONTROL SYSTEM
2469 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
2. INSPECT DRIVER'S POWER SEAT 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
4 ± GroundConstantContinuity
1 ± GroundConstantBattery positive voltage
If circuit is not as specified, inspect the circuits connected to oth-
er parts.
3. INSPECT PASSENGER'S POWER SEAT SWITCH
CONTINUITY
Slide switch:
Switch positionTester connectionSpecified condition
FRONT1 ± 9
4 ± 6Continuity
OFF4 ± 6
4 ± 9Continuity
BACK1 ± 6
4 ± 9Continuity
Front vertical switch:
Switch positionTester connectionSpecified condition
UP1 ± 5
4 ± 10Continuity
OFF4 ± 5
4 ± 10Continuity
DOWN1 ± 10
4 ± 5Continuity
Lifter switch:
Switch positionTester connectionSpecified condition
UP1 ± 8
4 ± 7Continuity
OFF4 ± 7
4 ± 8Continuity
DOWN1 ± 7
4 ± 8Continuity

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.

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.