Mitsubishi Montero (2002-2004). Manual - part 382

INPUT SIGNAL PROCEDURES

TSB Revision

SWS INPUT SIGNAL PROCEDURES

54Bc-75

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

SWS INPUT SIGNAL PROCEDURES

54Bc-76

.

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

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

SWS INPUT SIGNAL PROCEDURES

54Bc-77

DIAGNOSIS

Required Special Tools:

• MB991223: Harness Set

• MB991502: Scan Tool (MUT-II)

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 8.
Back door : Go to Step 14.
Driver's and front passenger's door : Go to Step 20.
Driver's and front passenger's door (Lock signal only) : 

Go to Step 22.

STEP 2. 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 3.
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.

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

INPUT SIGNAL PROCEDURES

TSB Revision

SWS INPUT SIGNAL PROCEDURES

54Bc-78

STEP 3. Check the ground circuit to the driver's door lock 
key cylinder switch. Test at driver's door lock key cylinder 
switch connector H-03.
(1) Disconnect driver's door lock key cylinder switch connector 

H-03 and measure the resistance available at the wiring 
harness side of the connector.

(2) Measure the resistance value between terminal 2 and 

ground.

• The resistance should equal 2 ohms or less.

Q: Is the measured resistance 2 ohms or less?

YES : Go to Step 6.
NO :  Go to Step 4.

STEP 4. 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 5.
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.

AC204180

CONNECTOR : H-03

AB

HARNESS SIDE

<DRIVER'S SIDE>

H-03(B)

H-03(B)

1

2

3

3

1

2

ACX01601AB

CONNECTOR H-03
(HARNESS SIDE)

AC204180

CONNECTOR : H-03

AB

HARNESS SIDE

<DRIVER'S SIDE>

H-03(B)

H-03(B)

1

2

3