Lexus SC300 / Lexus SC400. Manual - part 187

NG

OK

NG

OK

1

2

Check P/W fuse.

Check voltage between terminal +B2 of
ECU connector and body ground.

Check and repair harness and connectors
between ECU and battery

(See page 

IN–27

).

Check for short in all the harness
and components connected to the
DOOR fuse (See attached wiring
diagram). 

*1

Proceed to next circuit inspection
shown on matrix chart (See page

BE–371

).

WIRING DIAGRAM

*1:

The power source is supplied to the actuator
(door lock motor, luggage compartment door
opener motor) through the theft deterrent and
door lock ECU. Accordingly, if a short circuit of
the W/H or actuator occurs in the actuator circuit,
the DOOR fuse may become OPEN. so also in-
spect the actuator (door lock motor circuit on
page 

BE–380

, and the luggage compartment

door opener motor circuit on page 

BE–382

).

Actuator Power Source Circuit

      CIRCUIT DESCRIPTION

This circuit provides power to drive the door lock motor and the luggage compartment door opener mo-
tor.

      DIAGNOSTIC CHART

BE–378

–

BODY ELECTRICAL SYSTEM

Door Lock Control System

OK

NG

NG

OK

*1:  The power source is supplied to the actuator (door

lock motor, luggage compartment door opener mo-
tor) through the theft deterrent and door lock ECU.
Accordingly, if a short circuit of the W/H or actuator
occurs in the actuator circuit, the DOOR fusible link
may become OPEN, so also inspect the actuator
(door lock motor circuit on page 

BE–380

, and the

luggage compartment door opener motor circuit on
page 

BE–382

).

INSPECTION PROCEDURE

1

Check DOOR fuse.

C

OK

P

1.

Remove the No. 1 under cover and LH lower pad.

2.

Remove the DOOR fusible link from J/B No. 1.

Check continuity of DOOR fuse.

Continuity

Check for short in all the harness and components con-
nected to the DPPR fusible link (See attached wiring dia-
gram). *1

2

Check voltage between terminal +B2 of ECU connector and body ground.

C

OK

P

1.

Remove No. 1 under cover and heater duct.

2.

Disconnect the theft deterrent and door lock ECU
connector.

Measure voltage between terminal +B2 of ECU connec-
tor and body ground.

Voltage:

10 – 14 V

Proceed to next circuit inpsection shown on matrix chart
(See page 

BE–371

).

Check and repair harness and connectors be-

tween ECU and battery (See page 

IN–27

).

–

BODY ELECTRICAL SYSTEM

Door Lock Control System

BE–379

NG

Check operating sound of door lock
motor.

OK

NG

OK

Check door lock motor.

Check and harness connectors between ECU
and door lock motor (See page 

IN–27

).

Replace door lock motor.

1

2

WIRING DIAGRAM

Proceed to next circuit inspection
shown on matrix chart (See page

BE–371

).

Repair or replace door lock control
link.

Repair or replace harness or
connector.

3

OK

NG

Door Lock Motor Circuit

      CIRCUIT DESCRIPTION

The door lock motor locks and unlocks the door in accordance with signals from the ECU.

      DIAGNOSTIC CHART

HINT: Inspect the door which is malfunctioning.

BE–380

–

BODY ELECTRICAL SYSTEM

Door Lock Control System

NG

OK

NG

OK

OK

NG

INSPECTION PROCEDURE

1

Check operating sound of door lock motor.

C

OK

Hint

Check operating sound of door lock motor, when door
lock control switch is pushed to the lock side and unlock
side.

Can hear operating sound of door lock motor.

Inspect the door which is malfunctioning.

Repair or replace door lock control link.

2

Check door lock motor.

C

OK

Hint

P

1.

Remove the door trim and service hole cover.

2.

Disconnect the door lock motor connector.

1.

Connect positive

  

 lead to terminal 5 and nega-

tive 



 lead to terminal 2 o door lock motor connec-

tor.

2.

Connect positive 



 lead to terminal 2 and negative

 

lead to terminal 5 of, door lock motor connector.

1.

Door lock motor locks door.

2.

Door lock motor unlocks door.

Perform inspection in a short time (within 2 seconds).

Replace door lock motor.

3

Check harness and connectors between ECU and door lock motor (See page 

IN–27

).

Repair or replace harness or connector.

Proceed to next circuit inspection shown on ma-
trix chart (See page 

BE–371

).

–

BODY ELECTRICAL SYSTEM

Door Lock Control System

BE–381