Mitsubishi Colt Ralliart. Manual - part 566

TROUBLESHOOTING

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-102

Code No.69: Passenger's (front) seat belt pre-tensioner (squib) system (short-circuited to the earth)

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 passenger's (front) seat
belt pre-tensioner wire(s) are short-circuited to the
earth.

PROBABLE CAUSES

• Damaged wiring harnesses or connectors

• Short to the earth in the passenger's (front) seat

belt pre-tensioner (squib) harness

• Malfunction of the SRS-ECU

AC510233

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
(LH)

SRS-ECU

CONNECTOR
LOCK SWITCH

NOTE

: CONNECTOR COUPLED: ON
CONNECTOR UNCOUPLED: OFF

Passenger's (Front) Seat Belt Pre-tensioner (Squib)

Main

Index

Group

TOC

TROUBLESHOOTING

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-103

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 passenger's (front) seat belt

pre-tensioner connector C-20. Use a flat-tipped
screwdriver to pull out the locking button at the
harness side connector, and then disconnect the
connector.

(3) Connect special tool dummy resistor (MB991865)

to special tool resistor harness (MB991884).

(4) Connect special tool (MB991884) to the C-20

harness side connector.

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

the diagnosis code.

Q: Is diagnosis code 69 set?

YES : .

Go to Step 2.

NO : .

Replace the passenger's seat belt

pre-tensioner (Refer to

P.52B-159

STEP 2. Resistance measurement at the
SRS-ECU connector B-35
(1) Disconnect the negative battery terminal.

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

DANGER

To prevents the air bag from deploying unin-
tentionally, disconnect the passenger's
(front) seat belt pre-tensioner connector C-20
to short the squib circuit.

(3) Disconnect passenger's (front) seat belt

pre-tensioner connector C-20. Use a flat-tipped
screwdriver to pull out the locking button at the
harness side connector, and then disconnect the
connector.

AC207223 AE

Harness side
connector
(front view)

Connector: C-20

C-20 (B)

Centre

pillar

AC208430AE

Pre-tensioner

connector

Locking

button

Harness side

connector

Flat-tipped

screwdriver

AC201287BQ

C-20

Harness side
connector

MB991884

AC206285

B-35 (Y)

Connector: B-35

Harness side
connector
(rear view)

AC207223 AE

Harness side
connector
(front view)

Connector: C-20

C-20 (B)

Centre

pillar

AC208430AE

Pre-tensioner

connector

Locking

button

Harness side

connector

Flat-tipped

screwdriver

Main

Index

Group

TOC

TROUBLESHOOTING

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-104

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 B-35 harness

side connector terminals 5, 6 and body earth.

OK: Open circuit

Q: Is the check result normal?

YES : .

Go to Step 3.

NO : .

Repair the harness wires between

SRS-ECU connector B-35 (terminal No.5
and 6) and passenger's (front) seat belt
pre-tensioner connector C-20 (terminal No.1
and 2).

STEP 3. Check whether the diagnosis code is
reset.

Q: Is diagnosis code 69 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

13 14

16 17

19 20

5 6 7 8 9 10 11 12

1 2

3 4

AC208913

B-35 Harness side connector
(rear view)

Main

Index

Group

TOC

TROUBLESHOOTING

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-105

Code No.71: Side-airbag module (squib) (RH) system (short-circuited between terminals of the squib
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 sends an ignition sig-
nal. 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.

DIAGNOSIS CODE SET CONDITIONS

This diagnosis code is set if one side-airbag squib
(RH) wire shorted to the other. However, if no diag-
nosis 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 between the side-airbag module (RH)

(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-34 or C-25 is damaged or
improperly engaged, the short spring may not be
released when the connector is connected.

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.

AC510242

NOTE

CONNECTOR
COUPLED: ON
CONNECTOR
UNCOUPLED: OFF

CONNECTOR
LOCK
SWITCH

AIR BAG DRIVE
CIRCUIT

MICRO COMPUTER

SRS-ECU

SIDE-AIRBAG
MODULE
(SQUIB)
(RH)

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

CONNECTOR
LOCK
SWITCH

Side-airbag Module (RH) (Squib) Circuit

Main

Index

Group

TOC

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