Mitsubishi Montero (2004+). Manual — part 705

SYMPTOM PROCEDURES

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SIMPLIFIED WIRING SYSTEM (SWS)

54B-77

General circuit diagram for seat belt tone alarm function

General circuit diagram for RV meter operating sound function

SYMPTOM PROCEDURES

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SIMPLIFIED WIRING SYSTEM (SWS)

54B-78

INSPECTION PROCEDURE B-1: Tone Alarm: Ignition key reminder tone alarm function does not work
normally.

NOTE: This troubleshooting procedure requires the
use of scan tool MB991958 and SWS monitor kit
MB991862. For details on how to use the SWS mon-
itor, refer to "How to use SWS monitor

P.54B-10

."

.

CIRCUIT OPERATION
The ETACS-ECU operates the ignition key reminder
tone alarm function (sounds the tone alarm intermit-
tently), based on input signals from the following
switches:

• Ignition switch (IG1): OFF

• Key reminder switch: OFF

• Driver’s door switch: ON

The ETACS-ECU operates the ignition key reminder
tone alarm function (sounds the tone alarm intermit-
tently) if any of the following conditions are satisfied:

• Ignition switch: LOCK position (key inserted)

• Driver’s door: OPEN

.

TECHNICAL DESCRIPTION (COMMENT)
If the function does not work normally, the input cir-
cuit system from the switches or the ETACS-ECU
may be defective (refer to "CIRCUIT OPERATION").

.

TROUBLESHOOTING HINTS

• The key reminder switch may be defective

• The front door switches 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

• MB991813: SWS Monitor Kit

• MB991806: SWS Monitor Cartridge

• MB991812: SWS Monitor Harness (For Column-ECU)

• MB991822: Probe Harness

Ignition Key Reminder Tone Alarm Function

SYMPTOM PROCEDURES

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SIMPLIFIED WIRING SYSTEM (SWS)

54B-79

STEP 1. Use scan tool MB991958 to select "ECU COMM
CHK" on the SWS monitor display.

Check the ETACS-ECU.

CAUTION

To prevent damage to scan tool MB991958, always turn the
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting scan tool MB991958.
(1) Connect the special tool. Refer to "How to connect SWS

monitor

P.54B-7

(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 MB991958 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 MB991958 should show "OK" on the "ECU

COMM CHK" menu for the "ETACS ECU" menu.

Q: Is "OK" displayed on the "ETACS ECU" menu?

YES : Go to Step 2.
NO : Refer to Inspection Procedure A-3 "Communication

with ETACS-ECU is not possible

P.54B-42

."

AC309091

MB991911

MB991827

MB991824

AB

MB991806

MB991862

DATA LINK
CONNECTOR
(16-PIN)

DATA LINK
CONNECTOR
(13-PIN)

SYMPTOM PROCEDURES

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SIMPLIFIED WIRING SYSTEM (SWS)

54B-80

STEP 2. Check the input signal by using "FUNCTION
DIAG." menu of the SWS monitor.

Check the input signals from the following switches:

• Ignition switch: OFF (key inserted)

• Driver’s door: open

• Front passenger's door: closed

Operate scan tool MB991958 according to the procedure below
to display "KEY RMND. ALM."

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

Check that normal conditions are displayed on the items
described in the table below.
NOTE: The scan tool display changes when the driver's or the
front passenger's door is opened. If any of the doors is open,
the system can not be checked correctly.

Q: Are normal conditions displayed on the "IG SW (IG1)",

"FRONT DOOR SW" and "BUZZER"?
Normal conditions are displayed for all the items :

Replace the ETACS-ECU. The ignition key reminder
tone alarm function should now work normally.

The scan tool does not show the respective normal
condition for item "IG SW (IG1)." : Refer to Inspection

Procedure O-2 "ETACS-ECU does not receive any
signal from the ignition switch (IG1)

P.54B-505

."

The scan tool does not show the respective normal
condition for item "FRONT DOOR SW." : Refer to

Inspection Procedure O-5 "ETACS-ECU does not
receive any signal from the driver's or the front
passenger's door switch

P.54B-520

."

The scan tool does not show the respective normal
condition for item "BUZZER." : Go to Step 3.

ITEM NO.

ITEM NAME

NORMAL
CONDITION

ITEM 30

IG SW (IG1)

OFF

ITEM 32

FRONT DOOR SW

ON

ITEM 43

BUZZER

ON

AC309091

MB991911

MB991827

MB991824

AB

MB991806

MB991862

DATA LINK
CONNECTOR
(16-PIN)

DATA LINK
CONNECTOR
(13-PIN)