Mitsubishi Montero (2002-2004). Manual - part 256

SYMPTOM PROCEDURES

TSB Revision

SWS SYMPTOM PROCEDURES

54Bb-71

STEP 2. Check the input signal by using "DATA LIST" 
menu of the SWS monitor.
Turn the ignition switch to the "ON" position before checking 
input signals from the ignition switch (IG1).
Operate scan tool MB991502 according to the procedure below 
to display "ETACS ECU."

1. Select "SYSTEM SELECT."
2. Select "SWS."
3. Select "SWS MONITOR."
4. Select "DATA LIST."
5. Select "ETACS ECU."

Check that normal conditions are displayed on the items 
described in the table below.

Q: Is normal condition displayed on the "IG SW (IG1)"?

YES : Go to Step 3.
NO :  Refer to Inspection Procedure O-2 "ETACS-ECU 

does not receive any signal from the ignition switch 
(IG1) 

P.54Bc-7

."

STEP 3. Check the input signal (by using the pulse check 
mode of the monitor.)
Check input signal from the driver's side seat belt switch.
Operate scan tool MB991502 according to the procedure below 
to display "PULSE CHECK."

1. Select "SYSTEM SELECT."
2. Select "SWS."
3. Select "PULSE CHECK."

• When the driver's seat belt is unfastened, check if scan tool 

MB991502 sounds or not.

Q: Does scan tool MB991502 sound when the driver's side 

seat belt is unfastened?
Yes :  Replace the ETACS-ECU. Verify that the seat belt 

tone alarm function now works normally.

No :  Refer to Inspection Procedure P-3 "ETACS-ECU does 

not receive any signal from the driver's side seat belt 
switch 

P.54Bc-57

."

ITEM NO.

ITEM NAME

NORMAL CONDITION

ITEM 30

IG SW (IG1)

ON

AC204222AB

16-pin

13-pin

MB991502

MB991862

AC204222AB

16-pin

13-pin

MB991502

MB991862

SYMPTOM PROCEDURES

TSB Revision

SWS SYMPTOM PROCEDURES

54Bb-72

INSPECTION PROCEDURE B-4: Tone Alarm: RV meter operating sound function does not work 
normally.

NOTE: This troubleshooting procedure requires the 
use of scan tool MB991502 and SWS monitor kit 
MB991862. For details on how to use the SWS mon-
itor, refer to "How to use SWS monitor 

P.54Ba-8

."

.

CIRCUIT OPERATION
The ETACS-ECU sound a tone alarm when the RV 
meter sends a sound request signal to the ECU.

.

TECHNICAL DESCRIPTION (COMMENT)
If this function does not work normally, the RV meter, 
the ETACS-ECU or their communication circuit may 
be defective.

.

TROUBLESHOOTING HINTS

• The RV meter 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

• MB991502: Scan Tool (MUT-II) 

• MB991862: SWS monitor kit 

STEP 1. Check the RV meter.
Q: Does the RV meter work normally?

YES : Go to Step 2.
NO :  Check the RV meter. Refer to GROUP 54A, RV meter 

P.54A-199

.

RV Meter Annunciation Function

SYMPTOM PROCEDURES

TSB Revision

SWS SYMPTOM PROCEDURES

54Bb-73

STEP 2. Use scan tool MB991502 to select "ECU COMM 
CHK" on the SWS monitor display.
Check the following ECUs:

• ETACS-ECU

• RV meter

CAUTION

To prevent damage to scan tool MB991502, always turn the 
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting scan tool MB991502.
(1) Connect scan tool MB991502 to the data link connector 

(16-pin).

(2) Connect SWS monitor kit MB991862 to the data link 

connector (13-pin).

(3) Turn the ignition switch to the "LOCK" (OFF) position.
(4) Operate scan tool MB991502 according to the procedure 

below to display "ECU COMM CHK."

1. Select "SYSTEM SELECT."
2. Select "SWS."
3. Select "SWS MONITOR."
4. Select "ECU COMM CHK."

(5) Scan tool MB991502 should show "OK" on the "ECU 

COMM CHK" menus for both the "ETACS ECU" and the 
"CENTER DISP." menus.

Q: Is "OK" displayed on both the "ETACS ECU" and 

"CENTER DISP." menu?
"OK" are displayed for all the items : Go to Step 3.
"NG" is displayed on the "ETACS ECU" menu : Refer to 

Inspection Procedure A-3 "Communication with 
ETACS-ECU is not possible 

P.54Bb-25

."

"NG" is displayed on the "CENTER DISP." menu : Refer 

to Inspection procedure A-6 "Communication with RV 
meter is not possible 

P.54Bb-40

."

AC204222AB

16-pin

13-pin

MB991502

MB991862

SYMPTOM PROCEDURES

TSB Revision

SWS SYMPTOM PROCEDURES

54Bb-74

STEP 3. Check the input signal by using "FUNCTION 
DIAG." menu of the SWS monitor.
Turn the ignition switch to the "ON" position to check the input 
signals from the following switches.
Operate scan tool MB991502 according to the procedure below 
to display "CENTR. DIS. ALM."

1. Select "SYSTEM SELECT."
2. Select "SWS."
3. Select "SWS MONITOR."
4. Select "FUNCTION DIAG."
5. Select "BUZZER."
6. Select "CENTR. DIS. ALM."

When the RV meter display switch is operated, check that nor-
mal conditions are displayed on the items described in the table 
below.

Q: Are normal conditions displayed on the "BUZZER" and 

"beep data"?
YES : Replace the ETACS-ECU. Verify that the RV meter 

operating sound function works normally.

NO : 

• Normal condition is not displayed on the 

"BUZZER": Replace the ETACS-ECU. Verify that 
the RV meter operating sound function works 
normally.

• Normal condition is not displayed on the "beep 

data": Refer to Inspection Procedure O-10 
"ETACS-ECU does not receive signals from any 
control switches 

P.54Bc-46

."

CENTRAL DOOR LOCKING SYSTEM

GENERAL DESCRIPTION CONCERNING THE CENTRAL DOOR LOCKING SYSTEM

M1549021100088

The following ECUs affect the functions and control 
of the central door locking system.

ITEM NO.

ITEM NAME

NORMAL 
CONDITION

ITEM 43

BUZZER

ON

ITEM 60

beep data

ON (2 kHz)

AC204222AB

16-pin

13-pin

MB991502

MB991862

FUNCTION

CONTROL ECU

Door lock function

Operating the driver’s or front passenger’s door lock key 
cylinder

ETACS-ECU

Operating the driver’s or front passenger’s door lock switch
Operating the driver’s door inside lock knob

Door unlock function

Operating the driver’s door lock key cylinder
Operating the front passenger’s door lock key cylinder 
Operating the driver’s or front passenger’s door lock switch

Forgotten key prevention function