Mitsubishi Colt Ralliart. Manual — part 546

TROUBLESHOOTING

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-22

(5) Resistance measurement between C-09 curtain

air bag module (RH) side connector terminals 1
and 2.

OK: Open circuit

Q: Is the check result normal?

YES :

Replace the curtain air bag module (Refer

to

P.52B-152

).

NO :

Repair the harness wire between curtain air
bag module (RH) side connector C-09
(terminal No.1 and 2) and curtain air bag
module connector C-07 (terminal No.1 and
2).

STEP 7. Check whether the diagnosis code is
reset.

Q: Is diagnosis code 3A 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

).

Code No.3B: Curtain air bag module (squib) (RH) system (open-circuited in the squib circuit)

OPERATION

The SRS-ECU judges how severe a collision is by
detecting signals from the side impact sensors and
the side-airbag safing G-sensor. If the impact is over
a predetermined level, the SRS-ECU sends an igni-
tion signal. At this time, if the side-airbag safing
G-sensor is on, the curtain air bag module will
deploy.

DIAGNOSIS CODE SET CONDITIONS

This diagnosis code is set if curtain air bag module
squib <RH> wire(s) are open-circuited. However, if
no diagnosis code resets, the SRS warning lamp will
be switched off (diagnosis code will be retained).

PROBABLE CAUSES

• Improper connector contact

• Open circuit in the curtain air bag module (squib)

(RH) circuit

• Malfunction of the SRS-ECU

AC510221

CONNECTOR
LOCK
SWITCH

AIR BAG
DRIVE CIRCUIT

SRS-ECU

MICROC OMPUTER

CONNECTOR
LOCK
SWITCH

NOTE

CONNECTOR
COUPLED: ON
CONNECTOR
UNCOUPLED: OFF

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

CURTAIN AIR BAG
MODULE (SQUIB)
(RH)

Curtain Air Bag Module (Squib) (RH) Circuit

AB

Main

Index

Group

TOC

TROUBLESHOOTING

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-23

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) Disconnect intermediate connector C-09

(connection between curtain air bag wiring
harness and instrument panel wiring harness).

(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) Connect special tool (MB991866) to the C-09

harness side connector by backprobing.

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

the diagnosis code.

Q: Is diagnosis code 3B set?

YES :

Go to Step 2.

NO :

Go to Step 3.

STEP 2. Resistance measurement between
SRS-ECU connector B-34 (terminal No.29 and 30)
and harness side connector C-09 (terminal No.1
and 2).
(1) Disconnect the negative battery terminal.

(2) Disconnect SRS-ECU connector B-34.

(3) Disconnect intermediate connector C-09

(connection between curtain air bag wiring
harness and instrument panel wiring).

CAUTION

Do not insert a test probe into the terminal from
its front side directly as the connector contact
pressure may be weakened.

(4) Resistance measurement between the following

terminals.

• SRS-ECU connector B-34 terminal No.29 and

harness side connector C-09 terminal No.1

• SRS-ECU connector B-34 terminal No.30 and

harness side connector C-09 terminal No.2

OK: Continuity (Less than 2

Ω)

AC208385

Connector: C-09

C-09 (R)

Quarter panel

AD

Harness side

AC006042 CJ

MB991866
(Resistor harness)

C-09

Intermediate h

arness side

connector

C-09 Curtain air bag
module (RH) side connector

MB991865 (Dummy
resistor: 3

Ω)

AC206285

AG

B-34 (Y)

Connector: B-34

Harness side
connector
(rear view)

343536373839404142

252627282930313233

2122

2324

AC208385

Connector: C-09

C-09 (R)

Quarter panel

AD

Harness side

34 35 36 37 38 39 40 41 42

25 26 27 28 29 30 31 32 33

21 22

23 24

1 2

AC208818

B-34
Harness side
connector(rear view)

C-09 Harness side
connector

AC

Main

Index

Group

TOC

TROUBLESHOOTING

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-24

Q: Are the check results normal?

YES :

Go to Step 4.

NO :

Repair the harness wire between SRS-ECU
connector B-34 (terminal No.29 and 30) and
harness side connector C-09 (terminal No.1
and 2).

STEP 3. Resistance measurement between
curtain air bag module (RH) side connector C-09
(terminal No.1 and 2) and the curtain air bag
module C-07 (terminal No.1 and 2).

(1) Disconnect the negative battery terminal.

(2) Disconnect harness side connector C-09 and

curtain air bag module connector C-07, and
measure at the wiring harness side. For
connector C-07, use a flat-tipped screwdriver to
pull out the locking button at the harness side
connector, and then disconnect the connector.

(3) Connect C-07 harness side connector to special

tool resistor harness (MB991884).

CAUTION

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

terminals.

• Curtain air bag module (RH) side connector

C-09 terminal No.1 and special tool terminal
No.2

• Curtain air bag module (RH) side connector

C-09 terminal No.2 and special tool terminal
No.1

OK: Continuity (Less than 2

Ω)

Q: Are the check results normal?

YES :

Replace the curtain air bag module (Refer

to

P.52B-152

).

NO :

Repair the harness wire between curtain air
bag module (RH) side connector C-09
(terminal No.1 and 2) and curtain air bag
module connector C-07 (terminal No.1 and
2).

STEP 4. Check whether the diagnosis code is
reset.

Q: Is diagnosis code No.3B 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

).

AC401577

Connectors: C-07, C-09

C-07 (B)

Harness side
connector
(front view)

AE

C-09 (R)

C-07

C-09

AC208384 BJ

Locking button

C-07 Curtain air
bag module
connector

Flat-tipped
screwdriver

C-07 Harness side
connector

AC201287BR

C-07

Harness side
connector

MB991884

1 2

2

1

AC303565AE

Resister harness
connector

C-09 Curtain air bag module (RH)
side connector (rear view)

Main

Index

Group

TOC

TROUBLESHOOTING

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-25

Code No.3E: Curtain air bag module (squib) (RH) system (short-circuited to the power supply)

OPERATION

The SRS-ECU judges how severe a collision is by
detecting signals from the side impact sensors and
the side-airbag safing G-sensor. If the impact is over
a predetermined level, the SRS-ECU sends an igni-
tion signal. At this time, if the side-airbag safing
G-sensor is on, the curtain air bag module will
deploy.

DIAGNOSIS CODE SET CONDITIONS

This diagnosis code is set if the curtain air bag mod-
ule squib (RH) wire(s) are short-circuited to the
power supply.

PROBABLE CAUSES

• Damaged wiring harnesses or connectors

• Short to the power supply in the curtain air bag

module (squib) (RH) harness

• Malfunction of the SRS-ECU

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) Disconnect intermediate connector C-09

(connection between curtain air bag wiring
harness and instrument panel wiring harness).

AC510221

CONNECTOR
LOCK
SWITCH

AIR BAG
DRIVE CIRCUIT

SRS-ECU

MICROC OMPUTER

CONNECTOR
LOCK
SWITCH

NOTE

CONNECTOR
COUPLED: ON
CONNECTOR
UNCOUPLED: OFF

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

CURTAIN AIR BAG
MODULE (SQUIB)
(RH)

Curtain Air Bag Module (Squib) (RH) Circuit

AB

AC208385

Connector: C-09

C-09 (R)

Quarter panel

AD

Harness side

Main

Index

Group

TOC