Mitsubishi Lancer Evolution IX. Manual — part 645

TROUBLESHOOTING

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-93

DIAGNOSIS PROCEDURE

STEP 1. 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 69 set?

YES :

Go to Step 2.

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-94

STEP 2. Resistance measurement at the
SRS-ECU connector C-13

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

(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

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 C-13 harness

side connector terminals 27, 28 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 C-13 (terminal No.27
and 28) and passenger's (front) seat belt
pre-tensioner connector D-03 <LHD> or
D-16 <RHD> (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-109

).

NO :

An intermittent malfunction is suspected
(Refer to GROUP 00

− How to Use

Troubleshooting/Inspection Service Points

P.00-5

).

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

AC201663

34 35 36 37 38 39 40 41 42

25 26 27 28 29 30 31 32 33

2122

23 24

AK

C-13 Harness side
connector (rear view)

TROUBLESHOOTING

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-95

CHECK CHART FOR TROUBLE
SYMPTOMS

M1524003400611

Trouble

Inspection procedure No.

Reference page

Communication with M.U.T.-II MB991502 or
M.U.T.-III MB991955 is not possible
(Communication with all systems is not
possible).

−

GROUP 13A

−

Troubleshooting

P.13A-237

Communication with M.U.T.-II MB991502 or
M.U.T.-III MB991955 is not possible
(Communication is not possible with SRS).

1

P.52B-96

When the ignition switch is turned to the "ON"
position (engine stopped), the SRS warning
lamp does not illuminate.

Refer to diagnosis code No.43.

P.52B-60

After the ignition switch is turned to the "ON"
position, the SRS warning lamp does not go off
within approximately 7 seconds.

Refer to diagnosis code No.43.

P.52B-64

TROUBLESHOOTING

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-96

SYMPTOM PROCEDURES

INSPECTION PROCEDURE 1: Communication with M.U.T.-II MB991502 or M.U.T.-III MB991955 is not
possible (Communication is not possible with SRS).

OPERATION

• The SRS-ECU is powered from the ignition

switch (IG1).

• The SRS-ECU power is supplied from two cir-

cuits. Even if one circuit is shut off, the air bag
can inflate.

• The SRS system diagnosis can be done by con-

necting M.U.T.-II MB991502 or M.U.T.-III
MB991955 to the diagnosis connector.

IGNITION
SWITCH (IG1)

POWER SOURCE
CIRCUIT

BACK-UP
CAPACITOR

D.C.-D.C.
CONVERTER

MICROCOMPUTER

DIAGNOSIS
CONNECTOR

MUT INTERFACE
CIRCUIT

FRONT SIDE

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

SRS-ECU

NOTE

: LH drive vehicles
: RH drive vehicles

SRS-ECU Power Supply Circuit