Mitsubishi Lancer Evolution IX. Manual — part 632

TROUBLESHOOTING

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-41

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

diagnosis code.

Q: Is diagnosis code 28 set?

YES :

Go to Step 4.

NO :

The procedure is complete. It is assumed
that diagnosis code 28 set as connector
C-13, D-03 <LHD> or D-16 <RHD> was
engaged improperly.

STEP 4. Check the diagnosis code by connecting
a dummy resistor. (M.U.T.-II/III diagnosis code)
(1) Disconnect the negative battery terminal.

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

pre-tensioner connector D-03 <LHD> or D-16
<RHD>. 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 D-03

<LHD> or D-16 <RHD> harness side connector.

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

the diagnosis code.

Q: Is diagnosis code 28 set?

YES :

Go to Step 5.

NO :

Replace the passenger's (front) seat belt
with pre-tensioner (Refer to

P.52B-117

).

AC310465

AO

Connector: D-03
<LHD>

Harness side
connector
(front view)

D-03 (B)

AC310471

AJ

Connector: D-16
<RHD>

Harness side
connector
(front view)

D-16 (B)

AC300147AX

Flat-tipped
screwdriver

Locking button

D-03 <LHD>,
D-16 <RHD>
Passenger's (front)
seat belt
pre-tensioner
connector

D-03 <LHD>, D-16 <RHD>
Harness side connector

MB991884
MB991885

AC103283AY

D-03 <LHD>, D-16 <RHD>
Harness side connector

MB991884
(Resistor
Harness)

MB991865
(Dummy Resistor : 3 )

TROUBLESHOOTING

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-42

STEP 5. Resistance measurement at the
SRS-ECU connector C-13

(1) Disconnect SRS-ECU connector C-13.

DANGER

To prevents the air bag from deploying unin-
tentionally, disconnect the passenger’s
(front) seat belt pre-tensioner connector D-03
<LHD> or D-16 <RHD> to short the squib cir-
cuit.

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

pre-tensioner connector D-03 <LHD> or D-16
<RHD>. Use a flat-tipped screwdriver to pull out
the locking button at the harness side connector,
and then disconnect the connector.

CAUTION

Insert an insulator such as a cable tie to a depth
of 4 mm or more, otherwise the short spring will
not be released.
(3) Insert a cable tie [3 mm wide, 0.5 mm thick]

between terminals 27, 28 and the short spring to
release the short spring.

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 C-13 harness

side connector terminals 27 and 28.

OK: Open circuit.

Q: Is the check result normal?

YES :

Go to Step 6.

NO :

Repair the harness wires between
SRS-ECU connector C-13 (terminal No.7
and 8) and passenger’s (front) seat belt
pre-tensioner connector D-03 <LHD> or
D-16 <RHD> (terminal No.1 and 2).

AC101951

Connector: C-13

SRS-ECU

AL

C-13 (Y)

21

252627 282930 313233
34 35 3637 38394041 42

22

23 24

Harness side
connector
(rear view)

AC310465

AO

Connector: D-03
<LHD>

Harness side
connector
(front view)

D-03 (B)

AC310471

AJ

Connector: D-16
<RHD>

Harness side
connector
(front view)

D-16 (B)

AC300147AX

Flat-tipped
screwdriver

Locking button

D-03 <LHD>,
D-16 <RHD>
Passenger's (front)
seat belt
pre-tensioner
connector

D-03 <LHD>, D-16 <RHD>
Harness side connector

AC100393

AB

AQ

A

A

D-03 <LHD>, D-16 <RHD>
Harness side connector
(front view)

Terminal

Section
A - A

Cable tie

Short spring

4 mm or more

AC100326

34 35 36 37 38 39 40 41 42

25 26 27 28 29 30 31 32 33

21 22

23 24

AQ

C-13 Harness side
connector
(rear view)

TROUBLESHOOTING

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-43

STEP 6. Check whether the diagnosis code is
reset.

Q: Is diagnosis code 28 set?

YES :

Replace the SRS-ECU (Refer to

P.52B-109

).

NO :

An intermittent malfunction is suspected
(Refer to GROUP 00

− How to Use

Troubleshooting/Inspection Service Points

P.00-5

).

Code No.29: Passenger's (front) seat belt pre-tensioner (squib) system (open-circuited in the squib
circuit)

CONNECTOR
LOCK
SWITCH

CONNECTOR
LOCK
SWITCH

AIR BAG DRIVE CIRCUIT

MICROCOMPUTER

SRS-ECU

SEAT BELT
PRE-TENSIONER
(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 : Gray R : Red P : Pink V : Violet

NOTE

: CONNECTOR
COUPLED: ON
CONNECTOR
UNCOUPLED: OFF

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

TROUBLESHOOTING

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-44

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 outputs an
ignition signal. At this time, if the front air bag safing
G-sensor is on, the seat belt pre-tensioner will
deploy.

DIAGNOSIS CODE SET CONDITIONS

This diagnosis code is set if the passenger's (front)
seat belt pre-tensioner squib 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

• Open circuit in the passenger's (front) seat belt

pre-tensioner (squib) circuit

• Improper connector contact

• Malfunction of the SRS-ECU

CONNECTOR
LOCK
SWITCH

CONNECTOR
LOCK
SWITCH

AIR BAG DRIVE CIRCUIT

MICROCOMPUTER

SRS-ECU

SEAT BELT
PRE-TENSIONER
(LH)

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

NOTE

: CONNECTOR
COUPLED: ON
CONNECTOR
UNCOUPLED: OFF

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