Mitsubishi Outlander GS45X. Manual - part 1434

SRS AIR BAG DIAGNOSIS

TSB Revision

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-231

 DTC B1C35: Driver's Lap Pre-tensioner (Squib) System (Squib Circuit Open)

CAUTION

If DTC B1C35 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 lap pre-tensioner will deploy. 

.

DTC SET CONDITIONS

This DTC is set if there is abnormal resistance 
between the input terminals of the lap pre-tensioner 
(squib).

.

TROUBLESHOOTING HITS

• Improper connector contact

• Open circuit in the lap pre-tensioner (squib) cir-

cuit

• Malfunction of the SRS-ECU

SRS-ECU

Driver's Lap pre-tensioner (Squib) Circuit

CONNECTOR
LOCK SWITCH

LAP 
PRE-TENSIONER
(SQUIB)

CONNECTOR
LOCK SWITCH

: CONNECTOR CONNECTED: ON
  CONNECTOR DISCONNECTED: OFF

NOTE

AC901076

C-27 (Y)

AC

Connector: C-27

AC901079

Connector: D-24

AG

D-24 (B)

SRS AIR BAG DIAGNOSIS

TSB Revision

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-232

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-233

STEP 2. 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 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 lap pre-tensioner. (Using scan tool 
MB991958, read the diagnostic trouble code.)
(1) Disconnect the negative battery terminal.
(2) Disconnect lap pre-tensioner connector D-24. 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-24 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 B1C35 set?

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

(Refer to 

P.52B-457

). Then go to Step 5. 

ZC501967

AC404789

AC701411AB

MB991824

MB991827

MB991910

Data link 
connector

AC701629 AB

Harness side 
connector

Locking button

Flat-tipped 
screwdriver

Lap pre-tensioner

AC301553 BE

Harness side 
connector

MB991865

(Dummy resistor: 3    )

MB991884 

(Resistor harness)

SRS AIR BAG DIAGNOSIS

TSB Revision

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-234

STEP 4. Check the harness for open circuit between 
SRS-ECU connector C-27 (terminal No.35 and 36) and the 
lap pre-tensioner D-24 (terminal No.2 and 1).
(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-27 SRS-ECU connector.

DANGER

To prevent the lap pre-tensioner from deploying unin-
tentionally, disconnect the lap pre-tensioner connec-
tor D-24 to short the squib circuit.

(3) Disconnect SRS-ECU connector C-27 and lap 

pre-tensioner connector D-24, and measure at the wiring 
harness side. For connector D-24, 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.

CAUTION

Insert an insulator such as a cable tie to a depth of 4mm 
(0.16 inch) or more, otherwise the short spring will not be 
released.
(4) Insert a cable tie [3 mm (0.12 inch) wide, 0.5 mm (0.02 inch) 

thick] between terminals 35, 36 and the short spring to 
release the short spring.

AC507645

A

AC

Lock lever

AC701629 AB

Harness side 
connector

Locking button

Flat-tipped 
screwdriver

Lap pre-tensioner

AC507303AM

A

A

C-27 Harness side
connector (front view)

Section
A - A

Cable tie

Short spring

4 mm or more

Terminal