Mitsubishi Outlander (2013+). Manual - part 597

TROUBLESHOOTING

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-39

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III CAN bus diagnostics
Use the M.U.T.-III to diagnose the CAN bus lines.

Q: Is the check result normal?

YES : 

Go to Step 2.

NO : 

Repair the CAN bus line (Refer to GROUP 
54C, Diagnosis ).

STEP 2. Check whether the diagnosis code is 
reset.
Check again if the diagnosis code is set.
(1) Erase the diagnosis code.
(2) Ignition: "LOCK" (OFF) position to "ON"
(3) On completion, check that the diagnosis code is 

not reset.

Q: Is the diagnosis code 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 ).

STEP 3. Check of short to power supply, short to 
earth, and open circuit in FLH-, FLH+ line 
between SRS-ECU connector and front impact 
sensor (LH) connector.

NOTE: After inspecting intermediate connector 
inspect the wiring harness. If the intermediate con-
nector is damaged, repair or replace it.

Q: Is the check result normal?

YES : 

Go to Step 4.

NO : 

Repair the wiring harness.

STEP 4. Check the front impact sensor (LH).
(1) Disconnect the negative battery terminal.
(2) Alternate the front impact sensor (LH) and the 

front impact sensor (RH), and then install the 
alternated sensor.

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

check the diagnosis code.

Q: Is diagnosis code B1417 set?

YES : 

Replace the front impact sensor (LH) with a 

new one (Refer to 

P.52B-125

).

NO : 

Go to Step 5.

STEP 5. Check whether the diagnosis code is 
reset.

Q: Is diagnosis code B1417 set?

YES : 

Replace the SRS-ECU (Refer to 

P.52B-129

).

NO : 

An intermittent malfunction is suspected 
(Refer to GROUP 00, How to Cope with 
Intermittent Malfunction ).

Code No.B1418: Front impact sensor (LH) communication error

 

Code No.B1419: Front impact sensor (LH) communication impossible

CAUTION

If diagnosis code B1418 or B1419 is set in the 
SRS-ECU, always diagnose the CAN main bus 
line.

OPERATION

The front impact sensor (LH) transmits acceleration 
data to the SRS-ECU. The SRS-ECU then deter-
mines whether to operate the front air bags, and then 
outputs an ignition signal when necessary. The front 
impact sensor (LH) also diagnoses itself, and sends 
a diagnosis code to the SRS-ECU if a malfunction 
occurs

DIAGNOSIS CODE SET CONDITIONS

The diagnosis code is set if the communication 
between the left front impact sensor (LH) and 
SRS-ECU is abnormal (No. B1418), or impossible 
(No. B1419).

PROBABLE CAUSES

• Damaged wiring harnesses or connectors

• Malfunction of the front impact sensor (LH)

• Malfunction of the SRS-ECU

TROUBLESHOOTING

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-40

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III CAN bus diagnostics.
Use M.U.T.-III to diagnose the CAN bus lines.

Q: Is the check result normal?

YES : 

Go to Step 2

NO : 

Repair the CAN bus line (Refer to GROUP 
54C 

− Troubleshooting ).

STEP 2. Check whether the diagnosis code is 
reset.
(1) Connect the negative battery terminal.
(2) After erasing the diagnosis code memory, check 

the diagnosis code again.

(3) Disconnect the negative battery terminal.

Q: Is the diagnosis code No. B1418 or B1419 set?

YES : 

Go to Step 3

NO : 

Intermittent malfunction (Refer to GROUP 
00 

− How to Use 

Troubleshooting/Inspection Service Points 

− 

How to Cope with Intermittent Malfunction ).

STEP 3. Check the front impact sensor (LH).
(1) Check that the negative battery terminal is 

disconnected. If the negative battery terminal is 
connected, disconnect it.

(2) Alternate the front impact sensor (LH) and the 

front impact sensor (RH), and then install the 
alternated sensor.

(3) Connect the negative battery terminal.
(4) After erasing the diagnosis code memory, check 

the diagnosis code again.

(5) Disconnect the negative battery terminal.

Q: Is the diagnosis code No. B1418 or B1419 set?

YES : 

Replace the front impact sensor (LH) (Refer 

to 

P.52B-125

).

NO : 

Go to Step 4

STEP 4. Check of short to power supply, short to 
earth, and open circuit in FLH-, FLH+ line 
between SRS-ECU connector and front impact 
sensor (LH) connector.

NOTE: After inspecting intermediate connector 
inspect the wiring harness. If the intermediate con-
nector is damaged, repair or replace it.

Q: Is the check result normal?

YES : 

Go to Step 5

NO : 

Repair the wiring harness.

STEP 5. Check whether the diagnosis code is 
reset.

Q: Is the diagnosis code No. B1418 or B1419 set?

YES : 

Replace SRS-ECU (Refer to 

P.52B-129

).

NO : 

Intermittent malfunction (Refer to GROUP 
00 

− How to Use 

Troubleshooting/Inspection Service Points 

− 

How to Cope with Intermittent Malfunction ).

Code No.B1420 Right side-airbag module (squib) system (short circuit between squib terminals)

CAUTION

If the diagnosis code B1420 is set to SRS-ECU, 
be sure to diagnose the CAN bus line.

OPERATION

In case of side collision, when the impact exceeding 
the threshold is applied to the vehicle, and when the 
impact is simultaneously detected (turned ON) by the 
side impact sensor as well as by the analogue 
G-sensor in SRS-ECU, the electric current is sup-
plied from SRS-ECU to the side-airbag module 
(squib) of impacted side.

TROUBLE JUDGEMENT

The code is set when the short circuit occurs to 
between the terminals of SRS-ECU side-airbag mod-
ule (squib) circuit.

PROBABLE CAUSES

• Damaged short spring 

*

• Short circuit between terminals of side-airbag 

module (squib) circuit

• Damaged connector(s)

• Malfunction of SRS-ECU

NOTE: *: The squib circuit connectors integrate a 
short spring (which prevents the air bags from being 
unintentionally deployed because of static electricity 
by shorting the positive wire to the earth wire in the 
squib circuit when the connectors are disconnected). 
Therefore, when the above codes are set, the short 
spring may not be released due to the damaged con-
nector even when the connectors are connected.

TROUBLESHOOTING

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-41

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III CAN bus diagnostics.
Use M.U.T.-III to diagnose the CAN bus lines.

Q: Is the check result normal?

YES : 

Go to Step 2.

NO : 

Repair the CAN bus line (Refer to GROUP 
54C 

− Troubleshooting ).

STEP 2. Check whether the diagnosis code is 
reset.
(1) Connect the negative battery terminal.
(2) After erasing the diagnosis code memory, check 

the diagnosis code again.

(3) Disconnect the negative battery terminal.

Q: Is the diagnosis code No. B1420 set?

YES : 

Go to Step 3.

NO : 

Intermittent malfunction (Refer to GROUP 
00 

− How to Use 

Troubleshooting/Inspection Service Points 

− 

How to Cope with Intermittent Malfunction ).

STEP 3. Connector check: SRS-ECU, right 
side-airbag module.
(1) Check that the negative battery terminal is 

disconnected. If the negative battery terminal is 
connected, disconnect it.

AC905015

A

AC

Lock lever

(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. After disconnecting the SRS-ECU 

connector, connect it again.

AC706606

AC

Locking button

Side-airbag module
connector

(3) After disconnecting the right side-airbag module 

connector, connect the connector again. For the 
right side-airbag module connector 
disconnection, unlock the connector by sliding 
the locking button to the direction of the arrow as 
shown in the figure, and then disconnect the 
connector.

(4) Connect the negative battery terminal.
(5) After erasing the diagnosis code memory, check 

the diagnosis code again.

(6) Disconnect the negative battery terminal.

Q: Is the diagnosis code No. B1420 set?

YES : 

Go to Step 4.

NO : 

Replace the connector concerned.

STEP 4. Diagnosis check by dummy resistor 
connection.
(1) Check that the negative battery terminal is 

disconnected. If the negative battery terminal is 
connected, disconnect it.

AC706606

AC

Locking button

Side-airbag module
connector

(2) Disconnect the right side-airbag module 

connector, unlock the connector by sliding the 
locking button to the direction of the arrow as 
shown in the figure, and then disconnect the 

TROUBLESHOOTING

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-42

connector.

AC507310BS

Side-airbag 
module (RH) connector

Harness 
side connector

MB991865
(Dummy resistor: 3    )

MB991866 

(Resistor harness)

(3) Connect special tool dummy resistor (MB991865) 

to special tool resistor harness (MB991866).

CAUTION

Do not insert a probe directly into the terminal 
from the connector front side as the connector 
contact pressure may be weakened.
(4) Insert the resistor harness probe from the back of 

right side-airbag module harness side connector.

(5) Connect the negative battery terminal.
(6) After erasing the diagnosis code memory, check 

the diagnosis code again.

(7) Disconnect the negative battery terminal.

Q: Is the diagnosis code No. B1420 set?

YES : 

Go to Step 5.

NO : 

Replace the front seatback pad and frame 
assembly (Refer to 

P.52B-142

).

STEP 5. Resistance measurement at the 
SRS-ECU connector.
(1) Check that the negative battery terminal is 

disconnected. If the negative battery terminal is 
connected, disconnect it.

AC905015

A

AC

Lock lever

(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 SRS-ECU connector.

DANGER

To release the connector short spring in the 
following operations, disconnect this 
side-airbag module connector, and keep the 
squib circuit shorted.

AC706606

AC

Locking button

Side-airbag module
connector

(3) Disconnect the right side-airbag module 

connector, unlock the connector by sliding the 
locking button to the direction of the arrow as 
shown in the figure, and then disconnect the 
connector.

AC905468AR

A

A

Harness side
connector (front view)

Section
A - A

Cable tie

Short spring

4 mm or more

Terminal

CAUTION

The short spring may not be released due to the 
insufficient insertion, thus insert for 4 mm or 
more.
(4) Insert a cable tie (width: 3 mm, thickness: 0.5 

mm) between the SRS+, SRS- line and the short 
spring, and then release the short spring.

(5) Take the measurements below at the right 

side-airbag module harness side connector. 

• Continuity between SRS+, SRS- line

OK: No continuity

Q: Is the check result normal?

YES : 

Go to Step 6.

NO : 

Repair the wiring harness SRS+, SRS- line 
between the right side-airbag module 
connector and the SRS-ECU connector.