Lexus SC300 / Lexus SC400. Manual - part 1001

58

POWER SOURCE

HEADLIGHT RELAY (FOR USA)

1–2 : CLOSED WITH LIGHT CONTROL SW AT HEAD POSITION OR DIMMER SW AT FLASH POSITION

HEADLIGHT RELAY (FOR CANADA)

1–2  : CLOSED WITH LIGHT CONTROL SW AT HEAD POSITION OR DIMMER SW AT FLASH POSITION

: CLOSED WITH ENGINE RUNNING AND PARKING BRAKE PEDAL RELEASED (PARKING BRAKE SW OFF)

TAILLIGHT RELAY (FOR USA)

5–3 : CLOSED WITH LIGHT CONTROL SW AT TAIL OR HEAD POSITION

TAILLIGHT RELAY (FOR CANADA)

5–3 : CLOSED WITH LIGHT CONTROL SW AT TAIL OR HEAD POSITION

: CLOSED WITH ENGINE RUNNING AND PARKING BRAKE PEDAL RELEASED (PARKING BRAKE SW OFF)

IGNITION MAIN RELAY

2–1 : CLOSED WITH IGNITION KEY AT ON OR ST POSITION

I15

  IGNITION SW

4–3 : CLOSED WITH IGNITION KEY AT ACC OR ON POSITION
4–2 : CLOSED WITH IGNITION KEY AT ON OR ST POSITION
11–6: CLOSED WITH IGNITION KEY AT ON OR ST POSITION
4–1 : CLOSED WITH IGNITION KEY AT ST POSITION

: PARTS LOCATION

CODE

SEE PAGE

CODE

SEE PAGE

CODE

SEE PAGE

C23

28

I15

29

F 9

26

N 1

27

: RELAY BLOCKS

CODE

SEE PAGE

RELAY BLOCKS (RELAY BLOCK LOCATION)

2

19

ENGINE COMPARTMENT LEFT

4

23

LEFT KICK PANEL (J/B NO.1 LEFT)

: JUNCTION BLOCK AND WIRE HARNESS CONNECTOR

CODE

SEE PAGE

JUNCTION BLOCK AND WIRE HARNESS (CONNECTOR LOCATION)

1B

20

ENGINE ROOM MAIN WIRE

1J

20

COWL WIRE

1K

20

COWL WIRE

: CONNECTOR JOINING WIRE HARNESS AND WIRE HARNESS

CODE

SEE PAGE

JOINING WIRE HARNESS AND WIRE HARNESS (CONNECTOR LOCATION)

EB1

34

ENGINE WIRE AND ENGINE ROOM MAIN WIRE (FRONT SIDE OF R/B NO. 2)

IE1

36

ENGINE ROOM MAIN WIRE AND COWL WIRE (R/B NO. 4)

IJ1

36

ENGINE WIRE AND COWL WIRE (RIGHT KICK PANEL)

IJ2

36

ENGINE WIRE AND COWL WIRE (RIGHT KICK PANEL)

: GROUND POINTS

CODE

SEE PAGE

GROUND POINTS LOCATION

IF

36

LEFT KICK PANEL

: SPLICE POINTS

CODE

SEE PAGE

WIRE HARNESS WITH SPLICE POINTS

CODE

SEE PAGE

WIRE HARNESS WITH SPLICE POINTS

I 1

38

COWL WIRE

I24

38

ENGINE ROOM MAIN WIRE

I11

38

COWL WIRE

I33

38

ENGINE WIRE

SERVICE HINTS

122

POWER WINDOW

2

1H

10

1D

8

1J

1

1D

10

1D

9

1J

2

1B

5

1I

16

6

3

6

3

IF

IJ

IP1

20

IP1

15

B 4

8

3

1

1I

7

2

4

A

20

A

8

A

2

A

16

A

13

A

12

4

B

8

R

R

L–

W

B–

R

W–

B

W–

B

L

L

W–

B

R–

B

R–

W

W–

B

W–

B

W–

B

W–

B

R–

W

R–

W

W–

B

W–

B

W–

B

L

R–

W

R–

W

L

W–B

W–B

Y–R

10A
DOME

30A
DOOR

15A
ECU–IG

30A
POWER

KEY OFF POWER
CIRCUIT

POWER
MAIN
RELAY

D

OOR

O

P

E

N

DE

T

E

CT

IO

N

S

W

R

H

D

OOR

OP

E

N

DE

T

E

C

T

IO

N

S

W

L

H

THEFT DETERRENT
AND DOOR LOCK ECU

P

O

W

E

RW

IN

D

O

W

M

A

S

T

E

RA

N

D

DO

O

R

L

O

CK

C

O

NT

RO

L

S

W

L

H

D

OOR

L

OC

K

T 8

, T 9

B

A

1

2

1K

7

1K

13

FROM POWER SOURCE SYSTEM (SEE PAGE 56)

D1

0

D1

1

P5

6

2

5

1

123

UP

DO

W

N

M

UP

DO

W

N

3

4

2

IP1

2

IP1

3

IP1

11

IF2

11

IF2

3

M

2

1

9

10

5

7

5

1

R–

L

G–

W

R–

L

G–

W

G–

Y

R

R

G–

Y

R–

L

G–

W

L

L

L

L

POWER WINDOW MASTER AND
DOOR LOCK CONTROL SW LH

DRIVER’ S

PASSENGER’ S

LH

RH

DO

W

N

AU

T

O

UP

LOCK

NORMAL

S

R

Q

1

2

PO

W

ER

W

IN

D

O

W

CO

N

T

RO

L

S

W

R

H

POWER WINDOW
MOTOR RH

POWER WINDOW
MOTOR LH

P 7

P 6

P4

P 5

–

+

–

+

124

POWER WINDOW

WITH THE IGNITION SW TURNED ON, CURRENT FLOWS THROUGH THE ECU–IG FUSE 

→

  TERMINAL (A)2 OF THE THEFT

DETERRENT ECU

→

 (B)8 

→

 TERMINAL 2 OF THE POWER MAIN RELAY 

→

 TERMINAL 3

→

 TO GROUND, THIS ACTIVATES THE RELAY

AND THE CURRENT FLOWING TO TERMINAL 4 OF THE RELAY FROM POWER FUSE FLOWS TO TERMINAL 1 OF THE RELAY 

→

TERMINAL 4 OF THE POWER WINDOW MASTER SW, TERMINAL 3 OF THE POWER WINDOW SW.

1. MANUAL OPERATION (DRIVER’S WINDOW)

WITH THE IGNITION SW TURNED ON AND WITH THE POWER WINDOW MASTER SW (DRIVER’S) IN UP POSITION, THE CURRENT
FLOWING TO TERMINAL 4 OF THE POWER WINDOW MASTER SW FLOWS TO TERMINAL 10 OF THE MASTER SW 

→

 TERMINAL 1 OF

THE POWER WINDOW MOTOR 

→

 TERMINAL 2 

→

 TERMINAL 9 OF THE MASTER SW 

→

 TERMINAL 8 

→

 TO GROUND AND CAUSES

THE POWER WINDOW MOTOR TO ROTATE IN THE UP DIRECTION. THE WINDOW ASCENDS ONLY WHILE THE SW IS BEING PUSHED.

IN DOWN OPERATION, THE FLOW OF CURRENT FROM TERMINAL 4 OF THE POWER WINDOW MASTER SW TO TERMINAL 9 OF THE
MASTER SW CAUSES THE FLOW OF CURRENT FROM TERMINAL 2 OF THE MOTOR 

→

  TERMINAL 1 

→

  TERMINAL 10 OF THE

MASTER SW 

→

 TERMINAL 8 

→

 TO GROUND, FLOWING IN THE OPPOSITE DIRECTION TO MANUAL UP OPERATION AND CAUSING

THE MOTOR TO ROTATE IN REVERSE, LOWERING THE WINDOW.

2. DRIVER’S WINDOW AUTO DOWN OPERATION

WHEN THE DRIVER’S WINDOW SW IS PUSHED STRONGLY ON THE DOWN SIDE, THE CURRENT FLOWING TO TERMINAL 4 OF THE
POWER WINDOW MASTER SW FLOWS TO THE DOWN CONTACT POINT AND AUTO DOWN CONTACT POINT OF THE DRIVER’S SW.

THIS ACTIVATES THE RELAY (DOWN SIDE) INSIDE THE POWER WINDOW MASTER SW AND THE HOLD CIRCUIT ALSO TURNS ON AT
THE SAME TIME, SO THE RELAY (DOWN SIDE) REMAINS ACTIVATED EVEN WHEN THE SW IS RELEASED.

CURRENT FLOWS AT THIS TIME FROM TERMINAL 4 OF THE POWER WINDOW MASTER SW 

→

  TERMINAL 9 

→

  TERMINAL 2 OF

POWER WINDOW MOTOR 

→

 MOTOR 

→

 TERMINAL 1 

→

 TERMINAL 10 OF POWER WINDOW MASTER SW 

→

 TERMINAL 8 

→

 GROUND,

SO THE MOTOR CONTINUES TO OPERATE UNTIL THE DRIVER’S WINDOW IS FULLY DOWN.

WHEN THE DRIVER’S WINDOW FINISHES DOWN OPERATION THE HOLD CIRCUIT GOES OFF, SO THE RELAY (DOWN SIDE) ALSO
TURNS OFF. THIS STOPS THE CURRENT FLOW FROM TERMINAL 4 OF THE POWER WINDOW MASTER SW TO TERMINAL 9, SO THE
POWER WINDOW MOTOR STOPS AND AUTO DOWN OPERATION STOPS.

WHEN THE DRIVER’S SW IS PULLED ON THE UP SIDE DURING AUTO DOWN OPERATION, THE HOLD CIRCUIT IS TURNED OFF SO
CURRENT FLOW FROM TERMINAL 4 OF THE POWER WINDOW MASTER SW TO TERMINAL 9 IS CUT OFF AND THE POWER WINDOW
MOTOR STOPS. IF THE SW REMAINS PULLED UP THE RELAY (UP SIDE) IS ACTIVATED, SO CURRENT FLOWS FROM TERMINAL 4 OF
THE POWER WINDOW MASTER SW 

→

  TERMINAL 10 

→

  TERMINAL 1 OF POWER WINDOW MOTOR 

→

 MOTOR 

→

  TERMINAL 2 

→

TERMINAL 9 

→

  TERMINAL 8 

→

  GROUND,  THE POWER WINDOW MOTOR ROTATES IN THE UP DIRECTION AND MANUAL UP

OPERATION OCCURS WHILE THE SWITCH IS PULLED UP.

3. MANUAL OPERATION BY POWER WINDOW SW (PASSENGER’S WINDOW)

WITH POWER WINDOW SW (PASSENGER’S) PULLED TO THE UP SIDE, CURRENT FLOWING FROM TERMINAL 3 OF THE POWER
WINDOW CONTROL SW FLOWS TO TERMINAL 5 OF THE POWER WINDOW SW 

→

 TERMINAL 1 OF THE POWER WINDOW MOTOR 

→

TERMINAL 2 

→

 TERMINAL 1 OF THE POWER WINDOW SW 

→

 TERMINAL 2 

→

 TERMINAL 7 OF THE MASTER SW 

→

 TERMINAL 8 

→

 TO

GROUND AND CAUSES THE POWER WINDOW MOTOR (PASSENGER’S) TO ROTATE IN THE UP DIRECTION. UP OPERATION
CONTINUES ONLY WHILE THE POWER WINDOW SW IS PULLED TO THE UP SIDE. WHEN THE WINDOW DESCENDS, THE CURRENT
FLOWING TO THE MOTOR FLOWS IN THE OPPOSITE DIRECTION, FROM TERMINAL 2 TO TERMINAL 1, AND THE MOTOR ROTATES IN
REVERSE. WHEN THE WINDOW LOCK SW IS PUSHED TO THE LOCK SIDE, THE GROUND CIRCUIT TO THE PASSENGER’S WINDOW
BECOMES OPEN.

AS A RESULT, EVEN IF OPEN/CLOSE OPERATION OF THE PASSENGER’S WINDOW IS TRIED, THE CURRENT FROM TERMINAL 8 OF
THE POWER WINDOW MASTER SW IS NOT GROUNDED AND THE MOTOR DOES NOT ROTATE, SO THE PASSENGER’S WINDOW CAN
NOT BE OPERATED AND WINDOW LOCK OCCURS.

4. KEY OFF POWER WINDOW OPERATION

WITH THE IGNITION SW TURNED FROM ON TO OFF, THE THEFT DETERRENT ECU OPERATES AND CURRENT FLOWS FROM DOOR
FUSE TO TERMINAL (A)8 OF THE ECU OR DOME FUSE TO TERMINAL (A)20 OF THE ECU 

→

  TERMINAL (B)8 

→

  TERMINAL 2 OF

POWER MAIN RELAY 

→

 TERMINAL 3 

→

 TO GROUND FOR ABOUT 60 SECONDS. THE SAME AS NORMAL OPERATION, THE CURRENT

FLOWS FROM POWER FUSE 

→

 TERMINAL 4 OF THE POWER MAIN RELAY 

→

 TERMINAL 1 

→

 TERMINAL 4 OF THE POWER WINDOW

MASTER SW AND TERMINAL 5 OF THE POWER WINDOW SW. AS A RESULT, FOR ABOUT 60 SECONDS AFTER THE IGNITION SW IS
TURNED OFF, THE FUNCTIONING OF THIS RELAY MAKES IT POSSIBLE TO RAISE AND LOWER THE POWER WINDOW. ALSO, BY
OPENING THE FRONT DOOR (DOOR DETECT SW ON) WITHIN ABOUT 60 SECONDS AFTER TURNING THE IGNITION SW TO OFF, A
SIGNAL IS INPUT TO TERMINALS (A)12 OR (A)13 OF THEFT DETERRENT ECU. AS A RESULT, THE ECU TURNS OFF AND UP AND
DOWN MOVEMENT OF THE POWER WINDOW STOPS.

SYSTEM OUTLINE