Mitsubishi Outlander GS45X. Manual - part 1443

SRS AIR BAG DIAGNOSIS

TSB Revision

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-267

(5) Check for continuity between C-27 harness side connector 

terminals 43, 44 and body ground.
It should be an open circuit.

Q: Is it open circuit?

YES : Erase the diagnostic trouble code memory, and check 

the diagnostic trouble code. If DTC B1C47 sets, 
replace the SRS-ECU (Refer to 

P.52B-436

). Then go 

to Step 6.

NO :  Go to Step 5.

STEP 5. Check harness wires for short circuit to ground 
between SRS-ECU connector C-27 (terminal No.43 and 44) 
and passenger's seat belt pre-tensioner connector D-130 
(terminal No.2 and 1).
Q: Is the check result normal?

YES : Go to Step 6.
NO :  Repair the harness wires between SRS-ECU 

connector C-27 and passenger's seat belt 
pre-tensioner connector D-130. Then go to Step 6.

STEP 6. 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 B1C47 set?

YES : Return to Step 1.
NO :  The procedure is complete.

AC608812DH

C-27 Harness side 
connector (front view)

ZC501967

AC404789

AC701411AB

MB991824

MB991827

MB991910

Data link 
connector

SRS AIR BAG DIAGNOSIS

TSB Revision

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-268

DTC B1C48: Front Passenger's Seat Belt Pre-tensioner (Squib) System (Shorted to Squib Circuit 
Power Supply)

CAUTION

If DTC B1C48 is set in the SRS-ECU, always diag-
nose the CAN main bus line.

.

CIRCUIT OPERATION

The SRS-ECU judges how severe a collision is by 
detecting signals from the front impact sensors and 
the front air bag analog 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. 

.

DTC SET CONDITIONS

This DTC is set if there is abnormal resistance 
between the input terminals of the passenger's seat 
belt pre-tensioner (squib).

.

TROUBLESHOOTING HITS

• Damaged wiring harnesses or connectors

• Short to the power supply in the passenger's seat 

belt pre-tensioner (squib) harness

• Malfunction of the SRS-ECU

: CONNECTOR
  CONNECTED: ON
  CONNECTOR
  DISCONNECTED: OFF

NOTE

Seat Belt Pre-Tensioner (passenger's side) (Squib) Circuit

SRS-ECU

SEAT BELT 
PRE-TENSIONER 
(RH)

CONNECTOR 
LOCK 
SWITCH

CONNECTOR 
LOCK SWITCH

AC901076

C-27 (Y)

AC

Connector: C-27

AC901079

D-130 (B)

Connector: D-130

AI

SRS AIR BAG DIAGNOSIS

TSB Revision

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-269

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)

• MB991865: Dummy resistor

• MB991884: Resister harness

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-17

).

ZC501967

AC404789

AC701411AB

MB991824

MB991827

MB991910

Data link 
connector

SRS AIR BAG DIAGNOSIS

TSB Revision

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-270

STEP 2. 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 3.
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 3. Check the passenger's seat belt pre-tensioner. 
(Using scan tool MB991958, read the diagnostic trouble 
code.)
(1) Disconnect the negative battery terminal.
(2) Disconnect passenger's seat belt pre-tensioner connector 

D-130. Use a flat-tipped screwdriver to unlock the locking 
button at the harness side connector by withdrawing it 
toward you in two stages, and then disconnect the 
connector.

(3) Connect special tool MB991865 to special tool MB991884.
(4) Connect special tool MB991884 to the D-130 harness side 

connector.

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

diagnostic trouble code.

Q: Is DTC B1C48 set?

YES : Go to Step 4.
NO :  Replace the passenger's seat belt with pre-tensioner 

(Refer to 

P.52B-457

). Then go to Step 6.

ZC501967

AC404789

AC701411AB

MB991824

MB991827

MB991910

Data link 
connector

AC4701631 AB

Seat belt 
pre-tensioner

Locking 
button

Flat-tipped
screwdriver

Floor wiring harness side
connector (2-pin, black)

AC301553 BE

Harness side 
connector

MB991865

(Dummy resistor: 3    )

MB991884 

(Resistor harness)