Mitsubishi Montero (2004+). Manual - part 1171

SERVICE PRECAUTIONS

TSB Revision

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-19

SRS-ECU TERMINAL 
NO.

DESTINATION OF HARNESS

CORRECTIVE ACTION

1, 2, 3, 4

Instrument panel wiring harness 

→ 

Front wiring harness 

→ Front impact 

sensor

Correct or replace each wiring harness.

7

Instrument panel wiring harness

→ 

Ground

Correct or replace the instrument panel 
wiring harness.

8

Instrument panel wiring harness

→ SRS 

warning light

Correct or replace the instrument panel 
wiring harness.

9, 10

Instrument panel wiring harness 

→ Air 

bag module (Front passenger's side)

Correct or replace the instrument panel 
wiring harness.

11, 12

Instrument panel wiring harness 

→ 

Clock spring 

→ Air bag module 

(Driver's side)

Correct or replace each wiring harness. 
Replace the clock spring.

13

Instrument panel wiring harness 

→ 

Junction block (fuse No.8)

Correct or replace the instrument panel 
wiring harness.

16

Instrument panel wiring harness 
→Function block (fuse No.6)

Correct or replace the instrument panel 
wiring harness.

20

Instrument panel wiring harness 

→ 

Data link connector

Correct or replace the instrument panel 
wiring harness.

21, 22

Side-airbag wiring harness 

→ 

Side-airbag module (LH)

Correct or replace the side air bag 
wiring harness.

23, 24

Side-airbag wiring harness 

→ 

Side-airbag module (RH)

Correct or replace the side air bag 
wiring harness.

27, 28

Side-airbag wiring harness 

→ Floor 

wiring harness

→ Seat belt 

pre-tensioner (RH)

Correct or replace each wiring harness.

29, 30

Side-airbag wiring harness 

→ Floor 

wiring harness 

→ Seat belt 

pre-tensioner (LH)

Correct or replace each wiring harness.

34, 36

Side-airbag wiring harness 

→ Floor 

wiring harness 

→ Side impact sensor 

(LH)

Correct or replace each wiring harness.

40, 42

Side-airbag wiring harness 

→ Floor 

wiring harness

→ Side impact sensor 

(RH)

Correct or replace each wiring harness.

SRS AIR BAG DIAGNOSIS

TSB Revision

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-20

WARNING

•

Inspection of the SRS-ECU connector harness 
should be carried out by the following procedure. 
Insert the backprobing tool into connector from 
harness side (rear side), and connect the tester to 
backprobing tool. If any tool other than backprob-
ing tool is used, it may cause damage to the har-
ness and other components. Furthermore, 
measurement should not be carried out by touch-
ing the backprobing tool directly against the termi-
nals from the front of the connector. The terminals 
are plated to increase their conductivity, so if they 
are touched directly by the backprobing tool, the 
plating may break, which will decrease reliability.

•

The SRS components and seat belt with pre-ten-
sioner should not be subjected to heat, so 
removed the SRS-ECU, driver’s and front passen-
ger’s air bag modules, clock spring, side-airbag 
module, front impact sensor, side impact sensor, 
and seat belt pre-tensioner before drying or baking 
the vehicle after painting.

•

SRS-ECU, air bag module, clock spring, front 
impact sensor, side impact sensor: 93

°

C (200

°

F) 

or more

•

Seat belt with pre-tensioner 90

°

C (194

°

F) or 

more

•

After servicing the SRS system, check the warning 
light operation to make sure that the system func-
tions properly (Refer to 

P.52B-20

).

•

Make certain that the ignition switch is "LOCK" 
(OFF) position when the scan tool is connected or 
disconnected. 

•

If you have any questions about the SRS system, 
please contact the MMNA Tech Line.

SRS AIR BAG DIAGNOSIS

INTRODUCTION TO DIAGNOSIS

M1524005000374

The SRS system is controlled by the SRS-ECU. The 
SRS-ECU judges how severe a collision is by detect-
ing signals from the left and right side impact sen-
sors, front impact sensors, front air bag analog 
G-sensor, front air bag safing G-sensor and side-air-
bag safing G-sensor. If the impact is over a predeter-
mined level, the SRS-ECU sends an ignition signal. 
At this time, if the safing G-sensor is on, the SRS air 

bag will inflate. The SRS warning light in the combi-
nation meter alerts a malfunction of the SRS system. 
If the following symptoms occur even when the vehi-
cle has not been in a collision, there may be a mal-
function in the SRS system.

• The SRS warning light does not go off within 

approximately seven seconds after the ignition 
switch has been turned to the "ON" position.

• The SRS warning light does not illuminate when 

the ignition switch is turned to the "ON" position.

AC006195

SRS-HARNESS CONNECTOR

SRS-ECU HARNESS CONNECTOR
(REAR SIDE)

AB

SRS AIR BAG DIAGNOSIS

TSB Revision

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-21

Refer to the After-collision Diagnosis (Refer to 

P.52B-206

). when inspecting and servicing the vehi-

cle that has been in a collision.

TROUBLESHOOTING STRATEGY

M1524003100461

Use these steps to plan your diagnostic strategy. If 
you follow them carefully, you will be sure that you 
have exhausted all of the possible ways to find a 
SRS fault.
1. Gather information about the problem from the 

customer.

2. Verify that the condition described by the 

customer exists.

3. Check the vehicle for any SRS diagnostic trouble 

codes (SRS DTC).

4. If you cannot verify the condition but there are no 

SRS DTCs, the malfunction is intermittent. Refer 
to GROUP 00, How to use Troubleshooting 

− 

Inspection Service Points 

− How to Cope With 

Intermittent Malfunctions 

P.00-6

.

5. If there is a SRS DTC, record the code number, 

then erase the code from vehicle memory using 
scan tool MB991502.

6. Recreate the SRS DTC set conditions to see if the 

same SRS DTC will set again.

• If the same SRS DTC sets again, follow the 

Inspection Chart for DTC and find the fault.

• If you cannot get the same SRS DTC to set 

again, the malfunction is intermittent. Refer to 
GROUP 00, How to use Troubleshooting 

− 

Inspection Service Points 

− How to Cope With 

Intermittent Malfunctions 

P.00-6

.

DIAGNOSTIC FUNCTION

M1524013800115

HOW TO CONNECT THE SCAN TOOL

Required Special Tools:

• 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 (Vehicles without 

CAN communication system)

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. 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 MB991911 to special tool MB991824.
5. Connect special tool MB991911 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 scan tool MB991958 is the reverse of the 
connecting sequence, making sure that the ignition switch is at 
the "LOCK" (OFF) position.

AC307591 AB

MB991911

DATA LINK

CONNECTOR

MB991824

MB991827

SRS AIR BAG DIAGNOSIS

TSB Revision

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-22

HOW TO READ AND ERASE DIAGNOSTIC 
TROUBLE CODES

Required Special Tools:

• 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 (Vehicles without 

CAN communication system)

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.
NOTE: If the battery voltage is low, diagnostic trouble codes will 
not be set. Check the battery if scan tool MB991958 does not 
display.
1. Connect scan tool MB991958 to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. Select "Interactive Diagnosis" from the start-up screen.
4. Select "System select."
5. Choose "SRS-AIR BAG" from the "BODY" tab.
6. Select "MITSUBISHI."
7. Select "Diagnostic Trouble Code."
8. If a DTC is set, it is shown.
9. Choose "Erase DTCs" to erase the DTC.

SRS WARNING LIGHT CHECK

M1524004300413

1. Check that the SRS warning light illuminates when the 

ignition switch is in the "ON" position.

2. Check that it illuminates for approximately seven seconds 

and then goes out.

3. If not, check for DTC.

AC307591 AB

MB991911

DATA LINK

CONNECTOR

MB991824

MB991827

ACX01667

AT

TEMP

SRS

P
R
N
D

5
4
3
2
1

x1000r/min

2

3

4

5

6

7

8

1

AB

SRS WARNING LIGHT