Mitsubishi Evolution X. Manual — part 704

SRS AIR BAG DIAGNOSIS

TSB Revision

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-263

STEP 5. Recheck for diagnostic trouble code.
Check again if the DTC is set.
(1) Erase the DTC.
(2) Turn the ignition switch to "ON" position.
(3) Check if the DTC is set.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the DTC set?

YES : Go to Step 6.
NO : There is an intermittent malfunction such as poor

engaged connector(s) or open circuit (Refer to
GROUP 00, How to Cope with Intermittent
Malfunction

P.00-15

).

STEP 6. Resistance measurement at the C-37 SRS-ECU
connector.
(1) While pushing the part "A" indicated in the figure of the

harness side connector, turn the lock lever to the direction
of the arrow to release the lock lever, and disconnect the
C-37 SRS-ECU connectors.

(2) Take the measurements below at the C-37 wiring harness

side connectors. It should be less than 2 ohms.

• Continuity between C-37 wiring harness side connector

terminal No. 17 and body ground

Q: Does continuity exist?

YES : Go to Step 7.
NO : Repair the wiring harness between the C-37

SRS-ECU connector terminal No. 17 and the ground.

STEP 7. Measure the voltage at the C-36 SRS-ECU
connector.
(1) Disconnect the negative battery terminal.
(2) While pushing the part "A" indicated in the figure of the

harness side connector, turn the lock lever to the direction
of the arrow to release the lock lever, and disconnect the
C-36 SRS-ECU connector.

(3) Connect the negative battery terminal.
(4) Ignition switch: ON

AC506734

A

AD

Lock lever

AC608812

C-37 Harness side
connector (front view)

HA

AC507645

A

AC

Lock lever

SRS AIR BAG DIAGNOSIS

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SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-264

(5) Take the measurements below at the C-36 harness side

connector.

• Voltage between terminal No. 61/62 and body ground

OK: 9 V or more

Q: Is the measured voltage within the specified range?

YES : Go to Step 9.
NO : Go to Step 8.

STEP 8. Check the harness for open circuit between
SRS-ECU connector C-36 (terminal No.61 and 62) and the
ETACS-ECU connector C-313 (terminal No.4 and 2).
(1) Disconnect the negative battery terminal.
(2) Disconnect SRS-ECU connector C-36.
(3) While pushing the part "A" indicated in the figure of the

harness side connector, turn the lock lever to the direction
of the arrow to release the lock lever, and disconnect the
C-36 SRS-ECU connector.

(4) Disconnect the ETACS-ECU connector C-313.

(5) Check for continuity between the following terminals. It

should be less than 2 ohms.

<Fuse No.12>

• SRS-ECU connector C-36 (terminal No.62) and the

ETACS-ECU connector C-313 (terminal No.2)

<Fuse No.18>

• SRS-ECU connector C-36 (terminal No.61) and the

ETACS-ECU connector C-313 (terminal No.4)

Q: Does continuity exist?

YES : Go to Step 9.
NO : Replace the harness wire between SRS-ECU

connector C-36 and the ETACS-ECU connector
C-313.

AC608813

C-36 Harness side
connector (front view)

BL

AC507645

A

AC

Lock lever

AC608812GP

C-313 Harness side
connector (front view)

C-36 Harness side
connector (front view)

SRS AIR BAG DIAGNOSIS

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SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-265

STEP 9. Recheck for diagnostic trouble code.
Check again if the DTC is set.
(1) Erase the DTC.
(2) Turn the ignition switch to the "ON" position.
(3) Check if the DTC is set.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is DTC B212C <Fuse No.12 circuit> or B212D <Fuse

No.18 circuit> set?
YES : Replace the SRS-ECU (Refer to

P.52B-383

).

NO : There is an intermittent malfunction such as poor

engaged connector(s) or open circuit (Refer to
GROUP 00, How to Cope with Intermittent
Malfunction

P.00-15

).

DTC B2207: Occupant Restraint Controller Internal 1

DTC B2208: Occupant Restraint Controller Internal 2

DTC B2209: Occupant Restraint Controller Internal 3

DTC B220A: Occupant Restraint Controller Internal 4

DTC B220B: Occupant Restraint Controller Firing Stored Energy

DTC B220C: Occupant Restraint Controller Accelerometer 1

DTC B220D: Occupant Restraint Controller Accelerometer 2

CAUTION

If DTCs are set in the SRS-ECU, always diagnose
the CAN main bus line.

.

TROUBLE JUDGMENT

The above DTC is set if an abnormality is detected in the circuit
inside the SRS-ECU.

.

TROUBLESHOOTING HINTS

Malfunction of the SRS-ECU

DIAGNOSIS

Required Special Tools:

• MB991958: Scan Tool (M.U.T.-III Sub Assembly)

• MB991824: Vehicle Communication Interface (V.C.I.)

• MB991827: M.U.T.-III USB Cable

• MB991910: M.U.T.-III Main Harness A (Vehicles with

CAN communication system)

SRS AIR BAG DIAGNOSIS

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SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-266

STEP 1. Using scan tool MB991958, diagnose the CAN bus
line

CAUTION

To prevent damage to scan tool MB991958, always turn the
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting scan tool MB991958.
(1) Connect scan tool MB991958. Refer to "How to connect the

scan tool

P.52B-28

."

(2) Turn the ignition switch to the "ON" position.
(3) Diagnose the CAN bus line.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the CAN bus line found to be normal?

YES : Go to Step 2.
NO : Repair the CAN bus line (Refer to GROUP 54C,

Diagnosis

P.54C-14

).

STEP 2. Recheck for diagnostic trouble code.
Check again if the DTC is set.
(1) Turn the ignition switch to the "ON" position.
(2) Check if the DTC is set.
(3) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Are any "Stored" or "Active" DTCs output?

YES : Replace the SRS-ECU (Refer to

P.52B-383

).

NO : There is an intermittent malfunction such as poor

engaged connector(s) or open circuit (Refer to
GROUP 00, How to Cope with Intermittent
Malfunction

P.00-15

).

AC608435

Data link connector

MB991827

MB991824

MB991910

AB