Mitsubishi Colt Ralliart. Manual — part 554

TROUBLESHOOTING

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-54

DIAGNOSIS PROCEDURE

STEP 1. Check the diagnosis code by connecting
a dummy resistor. (M.U.T.-III diagnosis code)
(1) Disconnect the negative battery terminal.

(2) Unclip passenger’s (front) air bag module

connector B-06.

(3) Connect special tool dummy resistor (MB991865)

to special tool resistor harness (MB991866).

CAUTION

Do not insert a test probe into the terminal from
its front side directly as the connector contact
pressure may be weakened.
(4) Disconnect the passenger's (front) air bag

module connector B-06, and insert special tool
(MB991866) into the harness side connector by
backprobing.

(5) Connect the negative battery terminal.
(6) Erase the diagnosis code memory, and check the

diagnosis code.

Q: Is diagnosis code 25 set?

YES : .

Go to Step 2.

NO : .

Replace the passenger's (front) air bag

module (Refer to

P.52B-145

).

STEP 2. Resistance measurement between
SRS-ECU connector B-35 (terminal No.9 and 10)
and the passenger's (front) air bag module
connector B-06 (terminal No.1 and 2).
(1) Disconnect the negative battery terminal.

(2) Disconnect SRS-ECU connector B-35 and

passenger's (front) air bag module connector
B-06.

AC206286

Connector: B-06

2 1

Harness side
connector (front view)

B-06 (R)

AE

Glove box striker

AC300956 AN

MB991865
(Dummy resistor: 3 )

MB991866

(Resistor harness)

B-06
Passenger's (front)
air bag module connector

B-06

Harness side

connector

AC206285

AF

B-35 (Y)

Connector: B-35

Harness side
connector
(rear view)

AC206286

Connector: B-06

2 1

Harness side
connector (front view)

B-06 (R)

AE

Glove box striker

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TROUBLESHOOTING

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-55

CAUTION

Do not insert a test probe into the terminal from
its front side directly as the connector contact
pressure may be weakened.
(3) Resistance measurement between the following

terminals.

• SRS-ECU connector B-35 terminal No.9 and

the passenger’s (front) air bag module con-
nector B-06 terminal No.1

• SRS-ECU connector B-35 terminal No.10 and

the passenger’s (front) air bag module con-
nector B-06 terminal No.2

OK: Continuity (Less than 2

Ω)

Q: Are the check results normal?

YES :

Go to Step 3.

NO :

Repair the harness wires between
SRS-ECU connector B-35 (terminal No.9
and 10) and passenger’s (front) air bag
module connector B-06 (terminal No.1 and
2).

STEP 3. Check whether the diagnosis code is
reset.

Q: Is diagnosis code 25 set?

YES :

Replace the SRS-ECU (Refer to

P.52B-143

).

NO :

An intermittent malfunction is suspected
(Refer to GROUP 00, How to Cope with
Intermittent Malfunction

P.00-13

).

1 2

1 2

3 4

5 6 7 8 9 10 11 12

13 14 15 16

18 19 20

17

AC100349

B-35
Harness side
connector (rear view)

B-06 Harness side
connector (rear view)

AN

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TROUBLESHOOTING

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-56

Code No.26: Driver's pre-tensioner (squib) system (short-circuited between terminals of the squib
circuit)

OPERATION

The SRS-ECU judges how severe a collision is by
detecting signals from the front impact sensors and
the front air bag analogue G-sensor. If the impact is
over a predetermined level, the SRS-ECU sends an
ignition signal. At this time, if the front air bag safing
G-sensor is on, the pre-tensioner will deploy.

DIAGNOSIS CODE SET CONDITIONS

This diagnosis code is set if one driver’s pre-ten-
sioner squib wire shorted to the other. However, if no
diagnosis code resets, the SRS warning lamp will be
switched off (diagnosis code will be retained).

PROBABLE CAUSES

• Improper engaged connector or defective short

spring*

• Short circuit between the driver's seat belt

pre-tensioner (squib) circuit terminals

• Damaged connector(s)

• Malfunction of the SRS-ECU

NOTE: *: The squib circuit connectors integrate a
"short" spring (which prevents the air bag from
deploying unintentionally due to static electricity by
shorting the positive wire to the earth wire in the
squib circuit when the connectors are disconnected).
Therefore, if connector B-35 or C-28 is damaged or
improperly engaged, the short spring may not be
released when the connector is connected.

AC510230

Wire colour code
B : Black LG : Light green G : Green L : Blue W : White Y : Yellow SB : Sky blue
BR : Brown O : Orange GR : Grey R : Red P : Pink V : Violet

SEAT BELT
PRETENSIONER
(RH)

SRS-ECU

CONNECTOR
LOCK SWITCH

CONNECTOR
LOCK SWITCH

NOTE

: CONNECTOR COUPLED: ON
CONNECTOR UNCOUPLED: OFF

Driver's Seat Belt Pre-Tensioner (Squib)

AB

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TROUBLESHOOTING

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-57

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III diagnosis code.

Q: Is diagnosis code 34 set?

YES :

Go to Step 2.

NO :

Go to Step 3.

STEP 2. Connector lock check: SRS-ECU
connector B-35. (M.U.T.-III diagnosis code)
(1) Disconnect the negative battery terminal.

(2) Disconnect the connectors B-35 and then

reconnect them.

(3) Connector the negative battery terminal.
(4) Erase the diagnosis code memory, and check the

diagnosis code.

Q: Is diagnosis code 26 set?

YES :

Go to Step 4.

NO :

The procedure is complete. It is assumed
that diagnosis code 26 set as connector
B-35 was engaged improperly.

STEP 3. Connector lock check: SRS-ECU
connector B-35 and driver’s seat belt
pre-tensioner connector C-28. (M.U.T.-III
diagnosis code)
(1) Disconnect the negative battery terminal.

(2) Disconnect connectors B-35 or C-28, and then

reconnect them. For connector C-28, use a
flat-tipped screwdriver to pull out the locking
button at the harness side connector, and then
disconnect the connector.

(3) Connector the negative battery terminal.
(4) Erase the diagnosis code memory, and check the

diagnosis code.

Q: Is diagnosis code 26 set?

YES :

Go to Step 4.

NO :

The procedure is complete. It is assumed
that diagnosis code 26 set as connector
B-35 or C-28 was engaged improperly.

AC206285

AF

B-35 (Y)

Connector: B-35

Harness side
connector
(rear view)

AC206285

AF

B-35 (Y)

Connector: B-35

Harness side
connector
(rear view)

AC207222 AF

Harness side
connector
(front view)

Connector: C-28

C-28 (B)

Centre

pillar

AC208430AE

Pre-tensioner

connector

Locking

button

Harness side

connector

Flat-tipped

screwdriver

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