Lexus RX300 (MCU15). Service manual — part 139

I19153

2

1

LOCK

UNLOCK

Door Lock Cable

I19158

2

6

LOCK

UNLOCK

Door Lock Cable

I19155

6

2

LOCK

UNLOCK

Door Lock Cable

I07318

UNLOCK

3

2

I07316

LOCK

3

2

–

BODY ELECTRICAL

POWER DOOR LOCK CONTROL SYSTEM

BE–103

LEXUS RX300 (RM785E)

(c)

Disconnect the leads from terminals.

(d)

Approximately 60 seconds later, connect the positive (+)
lead from the battery to terminal 1 and the negative (–)
lead to terminal 2, and check that the door lock moves to
the LOCK position.

If operation is not as specified, replace the door lock assembly.

23.

Using an ammeter with a current–measuring probe:
INSPECT REAR DOOR PTC THERMISTOR OPERA-
TION

(a)

Connect the positive (+) lead from the battery to terminal
2 and the negative (–) lead to terminal 6.

(b)

Attach a current–measuring probe to either the positive
(+) lead or the negative (–) lead, and check that the cur-
rent changes from approximately 3.2 A to less than 0.5 A
within 20 to 70 seconds.

(c)

Disconnect the leads from terminals.

(d)

Approximately 60 seconds later, connect the positive (+)
lead from the battery to terminal 6 and the negative (–)
lead to terminal 2, and check that the door lock cable
moves to the LOCK position.

If operation is not as specified, replace the door lock assembly.

24.

Using an ammeter with a current–measuring probe:
INSPECT BACK DOOR PTC THERMISTOR OPERA-
TION

(a)

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

(b)

Attach a current–measuring probe to either the positive
(+) lead or the negative (–) lead, and check that the cur-
rent changes from approximately 3.2 A to less than 0.5 A
within 20 to 70 seconds.

(c)

Disconnect the leads from terminals.

(d)

Approximately 60 seconds later, reverse the polarity, and
check that the door lock moves to the LOCK position.

If operation is not as specified, replace the door lock assembly.

BE16H–03

I19234

RH Door Lock Assembly
D Double Locking Motor
D Double Locking Switch

LH Door Lock Assembly
D Double Locking Motor
D Double Locking Switch

Body ECU

Ignition Switch

Key Unlock Warning Switch

Driver Door ECU

Rear LH Door ECU

Passenger Door ECU

Back Door Key Lock
and Unlock Switch

Back Door Lock Motor

Back Door Unlock Detection Switch

LHD:

RHD:

Ignition Switch

Key Unlock Warning Switch

Body ECU

Rear RH Door ECU

Double Lock Control
Relay

BE–104

–

BODY ELECTRICAL

DOUBLE LOCKING SYSTEM

LEXUS RX300 (RM785E)

DOUBLE LOCKING SYSTEM

LOCATION

BE1E6–02

I19159

Door Lock Cable

UNLOCK
LOCK

–

BODY ELECTRICAL

DOUBLE LOCKING SYSTEM

BE–105

LEXUS RX300 (RM785E)

INSPECTION

1.

INSPECT DOUBLE LOCK SYSTEM FUNCTION

HINT:

S

In case of doing the following inspection, must open one of the windows of the doors.

S

To set the double lock, turn the ignition switch OFF, pull out the key, open the driver’s door and then
perform the lock operation on the wireless transmitter. Locking again within 5 sec, after the first locking
sets the double lock.

(a)

Check that the double lock is set.
(1)

With the glass window opened, set the double lock from the outside of a vehicle using a wireless
transmitter.

(2)

Check that the doors won’t open from the inside of the vehicle even operating the door lock knob
and inside door handle

(b)

Check that the double lock is released (Case 1).
(1)

Press the UNLOCK button on the wireless transmitter.

(2)

Check that the doors will open from the inside of the vehicle by operating the door knob and inside
door handle.

(c)

Check that the double lock is released (Case 2).
(1)

With the glass window opened, set the double lock from the outside of a vehicle using a wireless
transmitter.

(2)

Under this condition, insert the key into the ignition key cylinder, turn the ignition switch to ON
and check that the doors will open.

If you find any abnormal symptom in the check items of (a),(b) and (c), troubleshoot according to the Problem
Symptom Table.

2.

INSPECT DRIVER’S DOOR (LHD)/PASSENGER’S
DOOR (RHD) DOUBLE LOCK MOTOR OPERATION

(a)

Set the Door Lock to LOCK position by the locking cable.

(b)

Connect the positive (+) lead from the battery to terminal
5 and negative (–) lead to terminal 12, and check that the
Door Lock will not unlock by pulling the locking cable.
(Locking cable must return to LOCK position by the force
of spring when pulling the locking cable.)

(c)

Reverse the polarity and check that the Door Lock will un-
lock by pulling the locking cable.

If operation is not as specified, replace the door lock assembly.
3.

INSPECT DRIVER’S DOOR (LHD)/PASSENGER’S
DOOR (RHD) DOUBLE LOCK SWITCH CONTINUITY

Switch position

Tester connection

Specified condition

OFF (Double lock is re-

leased)

–

No continuity

ON (Double lock is set)

6 – 7

Continuity

If continuity is not as specified, replace the door lock assembly.

I19160

Door Lock
Cable

UNLOCK
LOCK

I19161

Door Lock
Cable

LOCK
UNLOCK

I19129

Wire Harness Side

BE–106

–

BODY ELECTRICAL

DOUBLE LOCKING SYSTEM

LEXUS RX300 (RM785E)

4.

INSPECT PASSENGER’S DOOR (LHD)/DRIVER’S
DOOR (RHD) DOUBLE LOCK MOTOR OPERATION

(a)

Set the Door Lock to LOCK position by the locking cable.

(b)

Connect the positive (+) lead from the battery to terminal
8 and negative (–) lead to terminal 9, and check that the
Door Lock will not unlock by pulling the locking cable.
(Locking cable must return to LOCK position by the force
of spring when pulling the locking cable.)

(c)

Reverse the polarity and check that the Door Lock will un-
lock by pulling the locking cable.

If operation is not as specified, replace the door lock assembly.
5.

INSPECT DRIVER’S DOOR (LHD)/PASSENGER’S
DOOR (RHD) DOUBLE LOCK SWITCH CONTINUITY

Switch position

Tester connection

Specified condition

OFF (Double lock is re-

leased)

–

No continuity

ON (Double lock is set)

6 – 7

Continuity

If continuity is not as specified, replace the door lock assembly.

6.

INSPECT REAR DOOR DOUBLE LOCK SWITCH CON-
TINUITY

Switch position

Tester connection

Specified condition

OFF (Double lock is

released)

–

No continuity

ON (Double lock is set)

3 – 9

Continuity

If continuity is not as specified, replace the door lock assembly.
7.

INSPECT REAR DOUBLE LOCK MOTOR OPERATION

(a)

Set the Door Lock to LOCK position by the locking cable.

(b)

Connect the positive (+) lead from the battery to terminal
7 and negative (–) lead to terminal 8, and check that the
Door Lock will not unlock by pulling the locking cable.
(Locking cable must return to LOCK position by the force
of spring when pulling the locking cable.)

(c)

Reverse the polarity and check that the Door Lock will un-
lock by pulling the locking cable.

If operation is not as specified, replace the door lock assembly.

8.

INSPECT DOUBLE LOCK DOOR CONTROL RELAY
CIRCUIT