Lexus SC300 / Lexus SC400. Manual - part 138

Troubleshooting

You will find the cause of trouble more easily by properly using the table shown below. In this table, the
numbers indicate the order of priority of the causes of trouble. Check each part in the order shown. If neces-
sary, replace the part.

See page

BE–4

,21

BE–4

,21

BE–4

,20

BE–4

,20

BE–156

BE–152

BE–149

BE–151

BE–152

BE–26

BE–392

BE–4

,20

     –

–

Part

name

Trouble

AM1 Fuse

DOME Fuse

DOOR Fuse

POWER Fuse

Theft Deterrent and Door Lock Control ECU

Power Window Main Relay

Power Window Master Switch

Power Window Switch

Power Window Motor

Ignition Switch

Door Open Detection Switch

ECU–IG Fuse

Wire Harness

*1

 Power window does not operate.

1

2

3

4

*2

 Power window does not operate.

3

5

4

6

7

2

1

8

“One Touch Power Window System” does
not operate.

1

Only one window glass does not move.

1

2

3

4

“Window Lock System” does not operate

1

“Window Lock Illumination” does not light
up.

1

Key–off power window does not operate

1

2

4

5

3

6

*1

: Dook Lock does not operate.

*2

: Dook Lock is normal.

–

BODY ELECTRICAL SYSTEM

Power Window Control System

BE–157

LIQUID CRYSTAL INNER MIRROR
SYSTEM

Description

The liquid crystal inner mirror replaces the previous mirror, which mechanically switched between the “Day” and
“Night” settings, with liquid crystal inside the mirror which changes the brightness of the mirror surface. The com-
ponent parts of this system and their functions are shown in the table below.

Parts Name

Function

Liquid Crystal Inner
Mirror

Receives current from the fuse DOME and changes the surface brightness of the mirror
when switch is operated.

Key Unlock Warning
Switch

Opens the circuit so that the mirror can be operated only when the ignition key is set.

Parts Location

BE–164

–

BODY ELECTRICAL SYSTEM

Liquid Crystal Inner Mirror System

Wiring and Connector Diagrams

Parts Inspection
(Liquid Crystal Inner Mirror)

REMOVAL AND INSTALLATION OF
LIQUID CRYSTAL INNER MIRROR

(See page 

BO–44

)

INSPECTION OF LIQUID CRYSTAL
INNER MIRROR

INSPECT LIQUID CRYSTAL INNER MIRROR

(a)  Using a screw driver, pry out the cover.
(b)  Remove two screws and center visor.

(Operation)
(a) Connect 

the positive (+) lead from the battery to terminal

1 and the negative (–) lead to terminal 2.

–

BODY ELECTRICAL SYSTEM

Liquid Crystal Inner Mirror System

BE–165

(b)  Press the mirror switch and check if the mirrors surface

repeatedly becomes ”bright” and ”dark”.

If operation is not as specified, replace the liquid crystal inner
mirror.

(Circuit)
Disconnect the inner mirror connector and inspect the con-
nector on the wire harness side as shown.

Check for

Tester connection

Condition

Specified value

Voltage

2–Ground

Constant

Battery voltage

Continuity

1 Ground

Ignition key set

Continuity

Continuity

1–Ground

Ignition key removed

No continuity

If circuit is not as specified, refer to 

BE–165

 wiring diagram

and inspect the circuits connected to other parts.

(Key Unlock Warning Switch)

(See page 

BE–26

)

Troubleshooting

You will find the cause of trouble more easily by properly using the table shown below. In this table, the numbers
indicate the order of priority of the cruses of trouble. Check each part in the order shown. If necessary, replace
the part.

See page

BE–4

,21

BE–165

BE–26

    –

–

Trouble

Parts

name

DOME Fuse

Liquid Crystal Inner Mirror

Key Unlock W

arning 

Switch

Wire Harness

Liquid Crystal Inner Mirror does not operate.

1

2

3

4

BE–166

–

BODY ELECTRICAL SYSTEM

Liquid Crystal Inner Mirror System