Mitsubishi Outlander GS45X. Manual - part 1393

SRS AIR BAG DIAGNOSIS

TSB Revision

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-67

DTC B1B03: Driver's Air Bag Module (1st squib) System (Short Circuit Between Squib Circuit 
Terminals)

 

DTC B1B07: Driver's Air Bag Module (2nd squib) System (Short Circuit Between Squib Circuit 
Terminals)

AC701509

SRS-ECU

DRIVER'S AIR BAG
MODULE (SQUIB)

CLOCK
SPRING 

Drivers's Air Bag Module (Squib) Circuit

*: CONNECTOR LOCK SWITCH
   CONNECTOR COUPLED: ON
   CONNECTOR UNCOUPLED: OFF

NOTE

AB

AC901076

C-28 (Y)

AB

Connector: C-28

AC900844

C-205 (Y)

C-207 (Y)

Connectors: C-205, C-207

AL

SRS AIR BAG DIAGNOSIS

TSB Revision

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-68

CAUTION

• If DTC B1B03 <1st squib> or B1B07 <2nd 

squib> is set in the SRS-ECU, always diag-
nose the CAN bus lines.

• When DTC B1B03 is set in the following diag-

nosis, check the 1st squib circuit. When DTC 
B1B07 is set, check the 2nd squib circuit.

.

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 SRS 
air bag will inflate. 

• The ignition signal is input to the air bag module 

via the clock spring to inflate the air bag.

.

DTC SET CONDITIONS

• This DTC is set if there is abnormal resistance 

between the input terminals of the driver's air bag 
module (squib). The most likely causes for this 
code to be set are the followings: 

• Short circuit in driver’s air bag module (squib) 

or harness

• Short circuit in the clock spring

.

TROUBLESHOOTING HINTS

• Improper engaged connector or defective short 

spring*

• Short circuit in the clock spring

• Short circuit between the driver's air bag module 

(squib) circuit terminals

• Damaged connector(s)

• Malfunction of the SRS-ECU

NOTE: *: The squib circuit connectors integrate a 
"short" spring (which prevents the air bag from 
deploying unintentionally due to static electricity by 
shorting the positive wire to the ground wire in the 
squib circuit when the connectors are disconnected). 
Therefore, if connector C-28, C-205 or C-207 is dam-
aged or improperly engaged, the short spring may 
not be released when the connector is connected.

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

• MB991866: Resister harness

SRS AIR BAG DIAGNOSIS

TSB Revision

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-69

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

).

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

).

ZC501967

AC404789

AC701411AB

MB991824

MB991827

MB991910

Data link 
connector

ZC501967

AC404789

AC701411AB

MB991824

MB991827

MB991910

Data link 
connector

SRS AIR BAG DIAGNOSIS

TSB Revision

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-70

STEP 3. Check SRS-ECU connector C-28, driver’s air bag 
module connector C-205 and clock spring connector 
C-207. (Using scan tool MB991958, read the diagnostic 
trouble code.)
(1) Disconnect the negative battery terminal.
(2) Disconnect connectors C-28, C-205 and C-207, and then 

reconnect them.

• While pushing the part "A" indicated in the figure of the 

harness side connector, turn the lock lever to the direc-
tion of the arrow to release the lock lever, and discon-
nect the C-28 SRS-ECU connector.

• Slide the outer housing of the clock spring side of 

driver’s air bag module connector C-205 in the arrow 
direction shown, and disconnect the connector.

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

diagnostic trouble code.

Q: Is DTC B1B03 <1st squib> or B1B07 <2nd squib> set?

YES : Go to Step 4.
NO :  The procedure is complete. It is assumed that DTC 

B1B03 <1st squib> or B1B07 <2nd squib> set 
because connector C-28, C-205 or C-207 was 
engaged improperly.

AC506734

A

AB

Lock lever

AC607302

AC600868

Outer housing of the driver's air bag 
module connector

Horn connector

Lower column 
cover

Driver's air bag 
module connector 
(4-pin, yellow)

AB