Lexus SC300 / Lexus SC400. Manual - part 220

Parts Inspection 

 – Interior Lights

(Integration Relay)

REMOVAL AND INSTALLATION OF
INTEGRATION RELAY

(See page 

BE–49

 )

INSPECTION OF INTEGRATION RELAY

INSPECT INTEGRATION RELAY

(Relay Circuit/Illuminated Entry System)
Remove the relay from junction block and inspect the con-
nector on the junction block side as shown in the chart.

Check for

Tester connection

Condition

Specified value

Continuity

A1–Ground

Driver’s or passenger’s courtesy

OFF (Door closed)

No continuity

y

A1–Ground

g

y

switch

ON (Door opened)

Continuity

A4–Ground

Passenger’s courtesy switch

OFF (Door closed)

No continuity

A4–Ground

Passenger’s courtesy switch

ON (Door opened)

Continuity

A6–Ground

Driver’s courtesy switch

OFF (Door closed)

No continuity

A6–Ground

Driver’s courtesy switch

ON (Door opened)

Continuity

A10–Ground

Constant

Continuity

Voltage

A1–Ground

Constant

*Battery voltage

g

A2–Ground

Constant

*Battery voltage

A10–Ground

Interior light switch

ON

*Battery voltage

A10–Ground

Interior light switch

OFF

No voltage

*: There is resistance because this circuit is grounded through the bulb.

If the circuit is as specified, try replacing the relay with a new
one.
If the circuit is not as specified, refer to 

BE–77

 wiring diagram

and inspect the circuits connected to other parts.

BE–78

–

BODY ELECTRICAL SYSTEM

Lighting System

(Courtesy Switch)

 REMOVAL AND INSTALLATION OF
COURTESY SWITCH

1. 

REMOVE COURTESY SWITCH
(a)  Remove door lock assembly.
(See page 

BO–36

)

(b)  Remove a screw.
(c)  Remove courtesy switch from door lock assembly.

2. 

INSTALL COURTESY SWITCH
For installation, follow the removal procedure in reverse.

INSPECTION OF COURTESY SWITCH

INSPECT COURTESY SWITCH

(Continuity)
Inspect the switch continuity between terminals.

If continuity is not as specified, replace the switch.
(Switch Circuit)
Disconnect the connector from the switch and inspect the
connector on the wire harness side as shown.

Check for

Tester connection

Condition

Specified value

Continuity

6–Ground

Constant

Continuity

Voltage

3–Ground

Constant

Battery voltage

If circuit is not as specified, inspect power source or wire
harness.

–

BODY ELECTRICAL SYSTEM

Lighting System

BE–79

(Front Personal Light Switch)

REMOVAL AND INSTALLATION OF
FRONT PERSONAL LIGHT

1. 

REMOVE FRONT PERSONAL LIGHT
(a)  Release eight tabs and remove the lens.
(b)  Remove three screws and separate front personal light.
(c)  Disconnect connector and remove front personal light.

2. 

INSTALL FRONT PERSONAL LIGHT
For installation, follow the removal procedure in reverse.

INSPECTION OF FRONT PERSONAL
LIGHT

INSPECT FRONT PERSONAL LIGHT SWITCH

(Continuity)
Inspect the light switch continuity between terminals.

If continuity is not as specified, replace the light assembly or
bulb.
(Switch Circuit)
Disconnect the connector from the switch and inspect the
connector on the wire harness side as shown.

Check for

Tester connection

Condition

Specified value

Voltage

3–Ground

Constant

Battery voltage

Continuity

1–Ground

Constant

Continuity

If circuit is not as specified, inspect power source or wire
harness.

BE–80

–

BODY ELECTRICAL SYSTEM

Lighting System

(Vanity Light Switch)

REMOVAL AND INSTALLATION  OF
VANITY LIGHT SWITCH

1. REMOVE 

VANITY 

LIGHT

(a)  Release two tabs and remove the lens.
(b)  Remove two screws and separate the vanity light from

sun visor.

(c)  Disconnect connector and remove vanity light.

2. 

INSTALL VANITY LIGHT
For installation follow the removal procedure in reverse.

INSPECTION OF VANITY LIGHT

INSPECT VANITY LIGHT SWITCH

(Continuity)
Inspect the vanity light continuity between terminals.

If continuity is not as specified, replace bulb or vanity light.
(Switch Circuit)
Disconnect the connector from the switch and inspect the
connector on the wire harness side as shown.

Check for

Tester connection

Condition

Specified value

Voltage

1–Ground

Constant

Battery positive voltage

Continuity

2–Ground

Constant

Continuity

If circuit is not as specified, inspect power source or wire har-
ness.

–

BODY ELECTRICAL SYSTEM

Lighting System

BE–81