Mitsubishi Montero Sport (2004+). Manual - part 490

SEAT BELT DIAGNOSIS

TSB Revision

INTERIOR

52A-5

1. Ensure that the ignition switch is at the "LOCK" (OFF) 

position.

2. Start up the personal computer.
3. Connect special tool MB991827 to special tool MB991824 

and the personal computer.

4. Connect special tool MB991910 to special tool MB991824.
5. Connect special tool MB991910 to the data link connector.
6. Turn the power switch of special tool MB991824 to the "ON" 

position.
NOTE: When special tool MB991824 is energized, special 
tool MB991824 indicator light will be illuminated in a green 
color.

7. Start the MUT-III system on the personal computer.

NOTE: Disconnecting the scan tool MB991958 is the 
reverse of the connecting sequence, making sure that the 
ignition switch is at the "LOCK" (OFF) position.

SYMPTOM CHART

M1523003000096

NOTE: When no input signals can be checked with the scan tool, there may be a malfunction in the diagnos-
tics circuit system.

AC305412

AB

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

SYMPTOM

INSPECTION 
PROCEDURE NO.

REFERENCE 
PAGE

When the seat belt is not fastened and the ignition switch is turned 
to the "ON" position, the seat belt tone alarm does not sound and 
the seat bet warning light does not illuminate or flash.

1

P.52A-6

When the seat belt is not fastened and the ignition switch is turned 
to the "ON" position, the seat belt warning light illuminates or 
flashes, but the seat belt tone alarm does not sound.

2

P.52A-11

When the seat belt is not fastened and the ignition switch is turned 
to the "ON" position, the seat belt tone alarm sounds, but the seat 
belt warning light does not illuminate or flash.

3

P.52A-16

After the ignition switch is turned to the "ON" position, the seat belt 
tone alarm does not stop sounding for 6 seconds, even though the 
seat belt is buckled immediately.

Refer to inspection 
procedure No.2

P.52A-11

SEAT BELT DIAGNOSIS

TSB Revision

INTERIOR

52A-6

SYMPTOM PROCEDURES

INSPECTION PROCEDURE 1: When the Seat Belt is not Fastened and the Ignition Switch is Turned to 
the "ON" Position, the Seat Belt Tone Alarm doed not Sound and the Seat Belt Warning Light does not 
Illuminate or Flash.

ETACS-ECU Power Supply Circuit

SEAT BELT DIAGNOSIS

TSB Revision

INTERIOR

52A-7

.

CIRCUIT OPERATION

• The ETACS-ECU powered from fusible link num-

ber 6.

• The ETACS-ECU can determine a position of the 

ignition switch by the ignition switch circuit volt-
age.

.

TECHNICAL DESCRIPTION (COMMENT)
The cause may be a malfunction of the ETACS-ECU 
power supply circuit system or of the ground circuit 
system.

.

TROUBLESHOOTING HINTS

• Malfunction of the ETACS-ECU

• Damaged wiring harnesses or connectors

DIAGNOSIS

STEP 1. Measure the power supply line voltage at the 
junction block connector D-11
(1) Remove the ETACS-ECU and measure at the junction 

block side.

(2) Voltage between terminal 2 and ground.

• The measured value should be approximately 9 volts or 

more.

Q: Does the measured voltage correspond with this range?

YES : Go to Step 3.
NO :  Go to Step 2.

AC003431

CONNECTOR: A-54X

A-54X

AC

AC003228AB

CONNECTORS: D-08, D-11, D-13

D-13

D-11

D-08

JUNCTION
BLOCK (REAR)

AC003227

JUNCTION
BLOCK (FRONT)

AE

CONNECTOR: D-01

D-01

AC003229

D-11 HARNESS CONNECTOR:
COMPONENT SIDE

AC

SEAT BELT DIAGNOSIS

TSB Revision

INTERIOR

52A-8

STEP 2. Check the harness wires between fusible link 
number 6 and ETACS-ECU connector D-11 (terminal No. 2).

NOTE: Check the intermediate connectors A-54X, D-01, and 
then the wiring harness. If the intermediate connectors A-54X 
and D-01 are damaged, repair or replace them. Refer to 
GROUP 00E, Harness Connector Inspection 

P.00E-2

. Then go 

to Step 7.
Q: Are the harness wires between fusible link number 6 

and ETACS-ECU connector D-11 (terminal No. 2) in good 
condition?
YES : Go to Step 7.
NO :  Repair it. Then go to Step 7.

STEP 3. Measure the ignition switch (IG1) line voltage the 
at the junction block connector D-11.
(1) Turn the ignition switch "ON." 

(2) Measure the voltage between terminal 3 and the ground.

• The measured value should be approximately 9 volts or 

more.

(3) Turn the ignition switch "LOCK" (OFF) position.
Q: Does the measured voltage correspond with this range?

YES : Go to Step 5.
NO :  Go to Step 4.

AC201084

JUNCTION 
BLOCK (REAR)

D-11

COMPONENT SIDE

AB

CONNECTOR: D-11

AC200774

2

1

CONNECTOR: A-54X

AB

A-54X

AC201083

5 4

9

10

11

12

2 1

6

7

3
8

AB

CONNECTOR: D-01

JUNCTION 
BLOCK (FRONT)

COMPONENT SIDE

D-01

AC003231

D-11
(JUNCTION BLOCK SIDE)

AB