Mitsubishi Montero (2004+). Manual - part 828

INPUT SIGNAL PROCEDURES

TSB Revision

SIMPLIFIED WIRING SYSTEM (SWS)

54B-569

STEP 18. Check the wiring harness between rear door 
switch (LH) connector F-09 (terminal 2) and ETACS-ECU 
connector D-222 (terminal 7).

NOTE: Also check intermediate connector D-125 and junction 
block connector D-217 for loose, corroded, or damaged termi-
nals, or terminals pushed back in the connector. If junction 
block connector D-217 or intermediate connector D-125 is 
damaged, Repair or replace the damaged component(s) as 
described in GROUP 00E, Harness Connector Inspection 

P.00E-2

.

Q: Is the wiring harness between rear door switch (LH) 

connector F-09 (terminal 2) and ETACS-ECU connector 
D-222 (terminal 7) in good condition?
YES : Replace the ETACS-ECU. If the functions, which are 

described in "CIRCUIT OPERATION", work normally, 
the input signal from the rear door switch (LH) should 
be normal.

NO :  The wiring harness may be damaged or the 

connector(s) may have loose, corroded or damaged 
terminals, or terminals pushed back in the connector. 
Repair the wiring harness as necessary. If the 
functions, which are described in "CIRCUIT 
OPERATION", work normally, the input signal from 
the rear door switch (LH) should be normal.

AC204174

CONNECTOR : D-222

AB

1

2

3

5

6

4

9 8

121110

13

15 14

16

17

7

19

20

18

JUNCTION BLOCK SIDE

D-222

AC204178

CONNECTOR : F-09

AC

HARNESS SIDE

1

2

3

F-09

AC204170

CONNECTOR : D-125

AO

9

8

6 7

5

3 4

20

32

21

33

43

17 18

30

41

16

29

28

39 40

13

25

12

24

35 36

14

26

37

15

27

38

19

31

42

1

10

22

2

11

23

34

AC204173

CONNECTOR : D-217

AG

HARNESS SIDE

8

1

11 10

3

4

12

9

2

13

14

6 5

15

7

D-217

INPUT SIGNAL PROCEDURES

TSB Revision

SIMPLIFIED WIRING SYSTEM (SWS)

54B-570

INSPECTION PROCEDURE P-5: ETACS-ECU does not receive any signal from the driver's, front 
passeger’s or back door lock key cylinder switch.

Door Lock Key Cylinder Switch Input Circuit

AC204171

CONNECTORS : D-15, D-111

AJ

D-111

D-15

AC204170

CONNECTOR : D-25

AZ

INPUT SIGNAL PROCEDURES

TSB Revision

SIMPLIFIED WIRING SYSTEM (SWS)

54B-571

.

CIRCUIT OPERATION
The ETACS-ECU operates the central door locking 
system according to signal from the driver's, front 
passenger’s or back door lock key cylinder switch.

.

TECHNICAL DESCRIPTION (COMMENT)
If the signal is not normal, the systems, which are 
described in "CIRCUIT OPERATION", do not work 
normally.

.

TROUBLESHOOTING HINTS

• The driver’s, front passenger’s or back door lock 

key cylinder switch may be defective

• The ETACS-ECU may be defective

• The wiring harness or connectors may have 

loose, corroded, or damaged terminals, or termi-
nals pushed back in the connector

DIAGNOSIS

Required Special Tools:

• MB991223: Harness Set

• MB991958: Scan Tool (MUT-III Sub Assembly)

• MB991824: Vehicle Communication Interface (V.C.I.)

• MB991827: MUT-III USB Cable

• MB991911: MUT-III Main Harness B

AC204174

CONNECTORS : D-223, D-224

D-224(B)

AI

D-223(B)

AC204179

CONNECTOR : G-11

AK

AC204180

CONNECTOR : H-03

H-03(B)

AF

AC204181

CONNECTOR : H-18

H-18(B)

AG

AC204182 AH

CONNECTOR : I-06

INPUT SIGNAL PROCEDURES

TSB Revision

SIMPLIFIED WIRING SYSTEM (SWS)

54B-572

STEP 1. Check which door lock key cylinder switch is 
defective.
Q: Which door lock key cylinder switch does not send a 

signal to the ECU?
Driver's door : Go to Step 2.
Front passenger's door : Go to Step 9.
Back door : Go to Step 15.
Driver's and front passenger's door : Go to Step 21.
Driver's and front passenger's door (Lock signal only) : 

Go to Step 23.

STEP 2. Check driver's door lock key cylinder switch 
connector H-03 for loose, corroded or damaged terminals, 
or terminals pushed back in the connector. 
Q: Is driver's door lock key cylinder switch connector H-03 

in good condition?
YES : Go to Step 3.
NO :  Repair or replace the damaged component(s). Refer 

to GROUP 00E, Harness Connector Inspection 

P.00E-2

. If the systems, which are described in 

"CIRCUIT OPERATION", work normally, the input 
signal from the driver's door lock key cylinder switch 
should be normal.

STEP 3. Check the driver's door lock key cylinder switch.
Disconnect driver's door lock key cylinder switch connector 
H-03. Then check continuity between the switch terminals.

Q: Is the driver's door lock key cylinder switch in good 

condition?
YES : Go to Step 4.
NO :  Replace the driver's door lock key cylinder switch. If 

the systems, which are described in "CIRCUIT 
OPERATION", work normally, the input signal from 
the driver's door lock key cylinder switch should be 
normal.

AC204180

CONNECTOR : H-03

AB

HARNESS SIDE

<DRIVER'S SIDE>

H-03(B)

H-03(B)

1

2

3

SWITCH 
POSITION

TESTER 
CONNECTION

SPECIFIED 
CONDITION

LOCK

2 

− 3

Less than 2 ohms

Neutral (OFF)

1 

− 2, 2 − 3

Open circuit

UNLOCK

1 

− 2

Less than 2 ohms

ACX02410

1

2

3