Mitsubishi Montero (2002-2004). Manual — part 815

SRS AIR BAG DIAGNOSIS

TSB Revision

SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DIAGNOSIS

52Bb-129

CIRCUIT OPERATION
The side impact sensor includes an analog G sensor
and CPU, etc. The CPU monitors the analog G sen-
sor output signal. If the CPU judges that the side-air-
bags should be deployed, it sends a fire signal to the
SRS-ECU to deploy the side-airbags. Besides that,
the CPU diagnoses the internal components of the
side impact sensor. If a malfunction occurs, it
requests the SRS-ECU to set a diagnostic trouble
code.

.

DTC SET CONDITIONS
These DTC are set if communication between the
side impact sensor (LH) and the SRS-ECU is not
possible or communication is faulty.

.

TROUBLESHOOTING HINTS

• Damaged wiring harnesses or connectors

• Malfunction of the side impact sensor (LH)

• Malfunction of the SRS-ECU

.

DIAGNOSIS

Required Special Tool:

• MB991502: Scan Tool (MUT-II)

STEP 1. Check the side impact sensor (LH).
(1) Disconnect the negative battery terminal.
(2) Replace the side impact sensor (LH) with the side impact

sensor (RH).

(3) Connect the negative battery terminal.
(4) Erase diagnostic trouble code memory, and then check the

diagnostic trouble code.

Q: Is DTC 89 or 96 set?

YES : Replace the side impact sensor (LH) with a new one.

(Refer to

P.52Ba-42

.) Then go to Step 3.

NO : Go to Step 2.

STEP 2. Check the harness wires for open circuit or short
circuit between SRS-ECU connector E-07 (terminal No.34
and 36) and side impact sensor (LH) connector F-13
(terminal No.1 and 2).
NOTE: After inspecting intermediate connector E-19 inspect
the wiring harness. If the intermediate connector E-19 is dam-
aged, repair or replace it. (Refer to GROUP 00E, Harness Con-
nector Inspection

P.00E-2

.) Then go to Step 3. If harness wires

are in good condition, go to Step 3. If any harness wires
between SRS-ECU connector E-07 and side impact sensor
(LH) connector F-13 are damaged, repair them or install the
sensor cable. Refer to

P.52Ba-42

. Then go to Step 3.

AC204603AC

CONNECTOR: E-19

FLOOR
CONSOLE

E-19

2

1

4

3

E-19

SRS AIR BAG DIAGNOSIS

TSB Revision

SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DIAGNOSIS

52Bb-130

Q: Are the harness wires between SRS-ECU connector E-

07 (terminal No.34 and 36) and side impact sensor (LH)
connector F-13 (terminal No.1 and 2) in good condition?
YES : Erase the diagnostic trouble code memory, and check

the diagnostic trouble code. If DTC 79 or 93 sets,
replace the SRS-ECU. (Refer to

P.52Ba-31

.) Then go

to Step 3.

NO : Repair the harness wires between SRS-ECU

connector E-07 and side impact sensor (LH)
connector F-13. Then go to Step 3.

STEP 3. Recheck for diagnostic trouble code.
Q: Is DTC 79 or 93 set?

YES : Return to Step 1.
NO : The procedure is complete. (If no malfunctions are not

found in all steps, an intermittent malfunction is
suspected. Refer to GROUP 00, How to Use
Troubleshooting/Inspection Service Points

− How to

Cope with Intermittent Malfunction

P.00-6

.)

ACX01478AJ

CONNECTOR: E-07

E-07 (Y)

34 35 36 37 38 39 40 41 42

25 26 27 28 29 30 31 32 33

21 22

23 24

HARNESS SIDE
CONNECTOR
(REAR VIEW)

AC204128

CONNECTOR: F-13

AC

F-13 (Y)

HARNESS
CONNECTOR:
HARNESS SIDE

FRONT SEAT

SIDE IMPACT
SENSOR

2

1

SRS AIR BAG DIAGNOSIS

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SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DIAGNOSIS

52Bb-131

DTC 81: Left Hand Side-Air Bag Module (Squib) System Fault 1 (Short Circuit between Terminals of
the Squib Circuit)

.

CIRCUIT OPERATION

• The SRS-ECU judges how severe a collision is

by detecting signals from the left and right side
impact sensors. If the impact is over a predeter-
mined level, the SRS-ECU outputs an ignition
signal. At this time, if the side-airbag safing G-
sensor is on, the SRS side-airbag will inflate.

• The ignition signal is input to the side-airbag

module to inflate the side-airbag.

.

DTC SET CONDITIONS
This DTC is set if there is abnormal resistance
between the input terminals of the side-airbag mod-
ule (LH) (squib).

.

TROUBLESHOOTING HINTS

• Improper engaged connector or defective short

bar*

• Short circuit between the left-side air bag module

(squib) circuit terminals

• Damaged connector(s)

• Malfunction of the SRS-ECU

AC204439AB

NOTE

: CONNECTOR LOCK SWITCH

CONNECTOR

CONNECTED: ON
CONNECTOR

DISCONNECTED: OFF

Side-Airbag Module (LH) (Squib) Circuit

ACX01478AI

CONNECTOR: E-07

E-07 (Y)

AC204635 AB

CONNECTOR: F-15

F-15 (R)

SRS AIR BAG DIAGNOSIS

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SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DIAGNOSIS

52Bb-132

.

NOTE: *: The squib circuit connectors integrate a
"short" bar (which prevents the air bag from deploy-
ing unintentionally due to static electricity by shorting
the positive wire to the ground wire in the squib cir-
cuit when the connectors are disconnected). (Refer
to

P.52Ba-2

.) Therefore, if connector E-07 or F-15

damaged or improperly engaged, the short bar may
not be released when the connector is connected.

.

DIAGNOSIS

Required Special Tools:

• MB991502: Scan Tool (MUT-II)

• MB991865: Dummy resister

• MB991866: Resister harness

STEP 1. Check the diagnostic trouble code.
Q: Is DTC 34 set?

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

STEP 2. Check SRS-ECU connector E-07.
Q: Is the connector correctly engaged?

YES : Go to Step 3.
NO : Engage the connector correctly. Then go to Step 7.

ACX01478AI

CONNECTOR: E-07

E-07 (Y)