Mitsubishi Colt Ralliart. Manual - part 573

TROUBLESHOOTING

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-130

DIAGNOSIS PROCEDURE

STEP 1. Check the harness wires for open circuit 
or short circuit between SRS-ECU connector 
B-34 (terminal No.40 and 42) and side impact 
sensor (RH) connector C-27 (terminal No.1 and 
2).

Q: Are the harness wires between SRS-ECU 

connector B-34 (terminal No.40 and 42) and side 
impact sensor (RH) connector C-27 (terminal No.1 
and 2) in good condition?
YES : . 

Go to Step 2.

NO : . 

Repair the harness wires between 

SRS-ECU connector B-34> (terminal No.40 
and 42) and side impact sensor (RH) 
connector C-27 (terminal No.1 and 2).

STEP 2. Check the side impact sensor (RH) 
(front). (M.U.T.-III diagnosis code)
(1) Disconnect the negative battery terminal.
(2) Replace the side impact sensor (RH) (front) with 

the side impact sensor (LH) (front).

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

the diagnosis code.

Q: Is diagnosis code 94 set?

YES : 

Replace the SRS-ECU (Refer to 

P.52B-143

).

NO : 

Replace the side impact sensor (LH) (front) 
with a new one (Refer to 

P.52B-157

). Go to 

Step 3 .

STEP 3. Check whether the diagnosis code is 
reset.

Q: Is diagnosis code 94 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

).

AC206285

AG

B-34 (Y)

Connector: B-34

Harness side 
connector 
(rear view)

343536373839404142

252627282930313233

2122

2324

AC401057

AK

Connector: C-27

C-27 (Y)

Harness side
(front view)

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TOC

TROUBLESHOOTING

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-131

CHECK CHART FOR TROUBLE SYMPTOMS

M1524003400989

Trouble

Inspection procedure No.

Reference page

Communication with M.U.T.-III is not possible 
(Communication with all systems is not 
possible).

−

GROUP 13A, 
Troubleshooting 

P.13A-235

GROUP 13B, 
Troubleshooting 

P.13B-242

Communication with M.U.T.-III is not possible 
(Communication is not possible with SRS).

1

P.52B-132

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-78

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-81

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TOC

TROUBLESHOOTING

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-132

SYMPTOM PROCEDURES

INSPECTION PROCEDURE 1: Communication with M.U.T.-III 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.-III to the diagnosis connector.

COMMENTS ON TROUBLE SYMPTOM

If communication is not possible with the SRS only, 
the cause is probably an open circuit in the diagnosis 
output circuit of the SRS or in the power circuit 
(including earth circuit).

PROBABLE CAUSES

• Damaged wiring harnesses or connectors

• Malfunction of the SRS-ECU

DIAGNOSIS PROCEDURE

STEP 1. Check that the M.U.T.-III can 
communicate with the other systems.

Q: Can the M.U.T.-III communicate with the other 

systems?
YES : 

Go to Step 2.

NO : 

Refer to GROUP 13A, Troubleshooting 

P.13A-235

, GROUP 13B, Troubleshooting 

P.13B-242

.

AC510262

IGNITION
SWITCH (IG1)

SRS-ECU

FRONT SIDE

DIAGNOSIS
CONNECTOR

FUSIBLE
LINK

6

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

SRS-ECU Power Supply Circuit

AB

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TROUBLESHOOTING

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-133

STEP 2. Resistance measurement between 
SRS-ECU connector B-35 (terminal No.20) and 
diagnosis connector B-32 (terminal No.7).
(1) Disconnect the negative battery terminal.

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

diagnosis connector B-32, and measure at the 
wiring harness side. 

CAUTION

Do not insert a test probe into the terminal from 
of the SRS-ECU connector B-35 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.20) 

and diagnosis connector B-32 (terminal No.7)

OK: Continuity (Less than 2 

Ω)

Q: Is the check results normal?

YES : . 

Go to Step 3.

NO : . 

Go to Step 5.

STEP 3. Resistance measurement the earth 
circuit to the SRS-ECU connector B-35.
(1) Disconnect the negative battery terminal.

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

measure at the wiring harness side.

CAUTION

Do not insert a test probe into the terminal from 
its front side directly as the connector contact 
pressure may be weakened.
(3) Check for continuity between terminal 19 and 

body earth.

OK: Continuity (Less than 2 

Ω)

Q: Is the check result normal?

YES : 

Go to Step 4.

NO : 

Check the harness wire for open circuit 
between SRS-ECU connector B-35 
(terminal No.19) and earth, and repair if 
necessary.

AC206285

AF

B-35 (Y)

Connector: B-35

Harness side 
connector 
(rear view)
 

AC313822 AC

Connector: B-32

Harness side 
(Front side)

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5 6 7 8 9 101112

1 2

3 4

1 2 3 4 5 6 7 8
9 10111213141516

AC006263

B-35 Harness side
connector (rear view)

Diagnosis 
connector 

AO

B-32

AC206285

AF

B-35 (Y)

Connector: B-35

Harness side 
connector 
(rear view)
 

AC209044

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5 6 7 8 9 101112

1 2

3 4

B-35 Harness side connector 
(rear view)

AE

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