Mitsubishi Outlander (2013+). Manual — part 608

TROUBLESHOOTING

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-83

PROBABLE CAUSES

• Malfunction of the passenger’s air bag cut off

switch

• Damaged wiring harnesses or connectors

• Malfunction of the SRS-ECU

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 lines (Refer to GROUP
54C, Diagnosis-Can Bus Diagnostic Chart ).

STEP 2. Check whether the diagnosis code is
reset.
Check again if the diagnosis code is set.
(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.B1570, B1573, B1574 or

B1575 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 passenger’s air bag cut off
switch.
Check of a passenger’s air bag cut off switch (Refer
to

P.52B-152

).

Q: Is the check result normal?

YES :

Go to Step 4.

NO :

Replace passenger’s air bag cut off switch
(Refer to

P.52B-150

.)

STEP 4. Check the passenger’s air bag cut off
switch circuit. Resistance measurement at
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.

(3) Switch the passenger’s air bag cut off switch to

air bag ON side.

(4) Measure the resistance between POF-, POFO

line.

OK: 820

± 20 Ω

(5) Switch the passenger’s air bag cut off switch to

air bag OFF side.

(6) Measure the resistance between POF-, POFO

line.

OK: Continuity (less than 2

Ω)

Q: Is the check result normal?

YES :

Go to Step 5.

NO :

Repair the harness wires POF-, POFO line
between SRS-ECU connector and
passenger’s air bag cut off switch
connector.

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.

B1574

Malfunction of the common terminal
or open circuit in its harness

B1575

Short to body earth in the common
terminal harness

Code No.

Symptom

TROUBLESHOOTING

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-84

(3) Disconnect the passenger’s air bag cut off switch

connector.

(4) Take the measurements below at the SRS-ECU

harness side connector.

• Continuity between POF-, POFO line and

body earth

OK: No continuity

Q: Is the check result normal?

YES :

Go to Step 6.

NO :

Repair the harness wires POF-, POFO line
between SRS-ECU connector and
passenger’s air bag cut off switch
connector.

STEP 6. Voltage 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.

(3) Disconnect the passenger’s air bag cut off switch

connector.

(4) Connect the negative battery terminal.
(5) Ignition switch: ON
(6) Take the measurements below at the SRS-ECU

harness side connector.

• Voltage between POF-, POFO line and body

earth

OK: 1 V or less

Q: Is the check result normal?

YES :

Go to Step 7.

NO :

Repair the harness wires POF-, POFO line
between SRS-ECU connector and
passenger’s air bag cut off switch
connector.

STEP 7. Check whether the diagnosis code is
reset.

Q: Is diagnosis code No.B1570, B1573, B1574 or

B1575 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.B1603 Seat belt pre-tensioner (driver’s side) (squib) system (short circuit between squib
circuit terminals)

CAUTION

If the diagnosis code B1603 is set to SRS-ECU,
be sure to diagnose the CAN bus line.

OPERATION

Only when the frontal impact exceeding the threshold
is simultaneously detected (turned ON) by the front
impact sensor as well as by the analogue G-sensor
in SRS-ECU, the electric current is supplied from
SRS-ECU to the seat belt pre-tensioner (squib).

TROUBLE JUDGEMENT

The code is set when the short circuit occurs
between the terminals of SRS-ECU seat belt pre-ten-
sioner (driver’s side) (squib) circuit.

PROBABLE CAUSES

• Damaged short spring

*

• Short circuit between terminals of seat belt

pre-tensioner (driver’s side) (squib) circuit

• Damaged connector(s)

• Malfunction of SRS-ECU

• Insufficient press of locking button or locking but-

ton not pressed

TROUBLESHOOTING

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-85

NOTE: *: The squib circuit connectors integrate a
short spring (which prevents the seat belt pre-ten-
sioner 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 connector even when the connectors
are connected.

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. B1603 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, seat belt
pre-tensioner (driver’s side).
(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.

ACC00046AB

Locking button

Flat-tipped
screwdriver

Seat belt pre-tensioner
harness side connector

(3) After disconnecting the seat belt pre-tensioner

(driver's side) harness side connector, connect
the connector again. For the seat belt
pre-tensioner (driver's side) harness side
connector disconnection, use the flat-tipped
screwdriver to pull out the harness side
connector locking button. After releasing the lock,
disconnect the harness side 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. B1603 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.

ACC00046AB

Locking button

Flat-tipped
screwdriver

Seat belt pre-tensioner
harness side connector

(2) Use the flat-tipped screwdriver to pull out the

locking button of harness side connector. After
releasing the lock, disconnect the seat belt
pre-tensioner (driver's side) harness side

TROUBLESHOOTING

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-86

connector.

AC301553DR

Harness side
connector

MB991865

(Dummy resistor: 3 )

MB991884

(Resistor harness)

(3) Connect special tool dummy resistor (MB991865)

to special tool resistor harness (MB991884).

(4) Connect special tool resistor harness to the seat

belt pre-tensioner (driver's side) 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. B1603 set?

YES :

Go to Step 5.

NO :

Replace the seat belt with pre-tensioner
(driver’s side) (Refer to

P.52B-147

).

STEP 5. Resistance check 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 SRS-ECU connector short
spring in the following operations, discon-
nect this seat belt pre-tensioner connector,
and keep the squib circuit shorted.

ACC00046AB

Locking button

Flat-tipped
screwdriver

Seat belt pre-tensioner
harness side connector

(3) Use the flat-tipped screwdriver to pull out the

locking button of harness side connector. After
releasing the lock, disconnect the seat belt
pre-tensioner (driver's side) harness side
connector.

AC905468AU

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. Therefore, insert the insu-
lator for 4 mm or more.
(4) Insert an insulator (width: 3 mm, thickness: 0.5

mm) such as cable tie between the PTD-, PTD+
line and the short spring, and release the short
spring.

(5) Take the measurements below at the SRS-ECU

harness side connector.

• Continuity between PTD-, PTD+ line

OK: No continuity

Q: Is the check result normal?

YES :

Go to Step 6.

NO :

Repair the wiring harness PTD-, PTD+ line
between the SRS-ECU connector and the
seat belt pre-tensioner (driver's side)
connector.