Lexus RX300 (MCU15). Service manual - part 350

I19265

Passenger Door ECU

LSWE

A–

A+

LSW

24

2

16

L–R

6

19

KL

KUL

13

L–Y

GR–R

GR

P

P–L

2 (*1)

D10 (*1)
D9 (*2)

Door Lock Motor

Door Unlock
Detection Switch

Door Key Lock and 
Unlock Switch

F17

4 (*2)

1 (*1)

3 (*2)

6 (*1)

7 (*2)

5 (*1)

8 (*2)

3 (*1)

2 (*2)

4 (*1)

1 (*2)

*1: LHD
*2: RHD

F17

F17

F17

F17

F17

Lock

Unlock

DI–632

–

DIAGNOSTICS

PASSENGER DOOR CONTROL SYSTEM

LEXUS RX300   (RM785E)

Door key lock and unlock switch circuit

CIRCUIT DESCRIPTION

The door key lock and unlock switch is built in the door key cylinder. When the key is turned to the lock side,
terminal 3 of the switch is grounded and when the key is turned to the unlock side, terminal 2 of the switch
is grounded.
Door key lock and unlock switch can be checked using DTC check. (Refer to DI–708)

WIRING DIAGRAM

DI2F1–07

–

DIAGNOSTICS

PASSENGER DOOR CONTROL SYSTEM

DI–633

LEXUS RX300   (RM785E)

INSPECTION PROCEDURE

1

Check the door key lock and unlock switch using DTC check 
(See page DI–708).

OK

Proceed to next circuit inspection shown on
problem symptoms table (See page DI–570).

NG

2

Check the door key lock and unlock switch (See page BE–97).

NG

Replace the door key lock and unlock switch.

NG

3

Check wireharness and connector between door key lock and unlock switch and
passenger door ECU.

NG

Repair or replace wireharness or connector.

OK

Proceed to next circuit inspection shown on
problem symptoms table 
(See page DI–570).

I03216

D6
Door Courtesy Light Front RH (*1)
D5
Door Courtesy Light Front LH (*2)

Passenger Door ECU

+B

11 (*1)
10 (*2)

2

1

CTYB

CYL

CTY

CTYE

D8 
Door Courtesy Switch RH (*1)
D7 
Door Courtesy Switch LH (*2)

F17

4

17

23

L–B

R–W

G–W

R–B

CPU

21

F17

F17

F17

10 (*1)
11 (*2)

*1: LHD
*2: RHD

DI–634

–

DIAGNOSTICS

PASSENGER DOOR CONTROL SYSTEM

LEXUS RX300   (RM785E)

Door courtesy light and courtesy switch circuit

CIRCUIT DESCRIPTION

The door courtesy switch goes on when the door is opened and goes off when door is closed.

WIRING DIAGRAM

DI2F2–09

–

DIAGNOSTICS

PASSENGER DOOR CONTROL SYSTEM

DI–635

LEXUS RX300   (RM785E)

INSPECTION PROCEDURE

1

Check operation of door courtesy light.

CHECK:
Check that door courtesy light comes on when door opened, and goes off when door is closed.
OK:
Must be operated normally.

OK

Proceed to next circuit inspection shown on
problem symptoms table (See page DI–570).

NG

2

Check courtesy light (See page BE–48).

NG

Replace the courtesy light.

OK

3

Check courtesy switch (See page BE–48).

NG

Replace the courtesy switch.

OK

4

Check wireharness and connector between courtesy light and passenger door
ECU, courtesy switch and passenger door ECU.

NG

Repair or replace wireharness or connector.

OK

Proceed to next circuit inspection shown on
problem symptoms table 
(See page DI–570).