Lexus LS400 (2000 year). Manual - part 24

I10509

Wire Harness Side

Connector ”A”

Connector ”B”

N07798

2

1

–

+

I09301

2

1

I09300

2

1

BE–178

–

BODY ELECTRICAL

POWER SEAT CONTROL SYSTEM (w/o Driving 
Position Memory)

2041

16.

INSPECT REAR 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, as
shown.

Tester connection

Condition

Specified condition

B7 – Ground

Constant

Continuity

B8 – Ground

Constant

Battery positive voltage

If circuit is not as specified, inspect the circuits connected to oth-
er parts.

17.

INSPECT SLIDE MOTOR OPERATION

(a)

Connect the positive (+) lead from the battery to terminal
2 and the negative (–) lead to terminal 1 and check that
the motor turns counterclockwise.

(b)

Reverse the polarity and check that the motor turns clock-
wise.

If operation is not as specified, replace the motor.

18.

INSPECT SLIDE MOTOR PTC THERMISTOR OPERA-
TION

(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 battery negative (–) terminal,
then move the seat to front position.

(b)

Continue to apply voltage and check that the current
changes to less than 1 ampere with 4 to 90 seconds.

(c)

Disconnect the lead from terminals.

(d)

Approximately 60 seconds later , connect the positive (+)
lead from battery to terminal 1 and the negative (–) lead
to terminal 2 and check that the seat begins to move back-
wards.

If operation is not as specified, replace the motor.

I09261

2

1

2

1

(a)

(b)

I09282

To ”DOWN”

1

2

I09281

1

2

–

BODY ELECTRICAL

POWER SEAT CONTROL SYSTEM (w/o Driving 
Position Memory)

BE–179

2042

19.

INSPECT HEADREST MOTOR OPERATION 
(For vertical)

(a)

Connect the positive (+) lead from the battery to terminal
2 and the negative (–) lead to terminal 1, and check that
the motor turns counterclockwise.

(b)

Reverse the polarity, and check that the motor turns
clockwise.

If operation is not as specified, replace the motor.

20.

INSPECT HEADREST MOTOR CIRCUIT BREAKER
OPERATION (For vertical)

(a)

Connect the positive (+) lead from the battery to terminal
1 and negative (–) lead to terminal 2 on the motor connec-
tor and move the headrest to DOWN position.

(b)

Continue to apply voltage, check that there is a circuit
breaker operation noise within 4 to 60 seconds.

(c)

Reverse the polarity check that the headrest begins to
move UP side within approx. 60 seconds.

If operation is not as specified, replace the headrest.

I09283

FRONT

2

4

3

1

REAR

BE–180

–

BODY ELECTRICAL

POWER SEAT CONTROL SYSTEM (w/o Driving 
Position Memory)

2043

21.

INSPECT HEADREST MOTOR OPERATION 
(For turning)

(a)

Connect the positive (+) lead from the battery to terminal
2 and negative (–) lead to terminal 4.

(b)

Connect the negative (–) lead to each terminal and check
that the headrest turns at each position, as shown in the
chart.

Tester connection

Position

1

FRONT

3

REAR

If operation is not as specified, replace the headrest.

BE0B6–01

I03259

Engine Room Junction Block
and Engine Room No.1 Relay Block

Engine Room
No.2 Relay Block

Instrument Panel Junction Block

BE–18

–

BODY ELECTRICAL

POWER SOURCE

1881

POWER SOURCE

LOCATION