Subaru Impreza 3 / Impreza WRX / Impreza WRX STI. Manual — part 641

AB(diag)-103

Diagnostic Chart with Trouble Code

AIRBAG SYSTEM (DIAGNOSTICS)

AV:DTC 6B BELT PRETENSIONER LH FAILURE

DTC DETECTING CONDITION:

• Seat belt pretensioner (LH) circuit is shorted.

• Pretensioner (LH) is faulty.

• Pretensioner harness (LH) is faulty.

• Airbag control module is faulty.
CAUTION:

• Before diagnosing the airbag system, be sure to turn the ignition switch to OFF, disconnect the

ground cable from battery, and wait 60 seconds or more before starting to work.

• When replacing the airbag module, seat belt pretensioner, roll connector, control module and sen-

sor, reconnect each part and check that the airbag warning light operates properly.

• When inspecting the airbag main harness, disconnect the airbag module connectors of the driver’s

and passenger’s seats for safety.

• When inspecting the airbag rear harness, disconnect the side airbag module connector, curtain

airbag module connector and seat belt pretensioner connector for safety reasons.

WIRING DIAGRAM:

Airbag system <Ref. to WI-82, WIRING DIAGRAM, Airbag System.>

Step

Check

Yes

CHECK POOR CONTACT OF CONNEC-
TORS.
Check for poor contact of the connectors
between the airbag control module and the seat
belt pretensioner LH.

Is there poor contact?

Replace the airbag
rear harness along
with body harness.

Go to step

CHECK SEAT BELT PRETENSIONER.
1) Turn the ignition switch to OFF, disconnect
the battery ground cable, and wait for 60 sec-
onds or more.
2) Disconnect the connector (AB21) from seat
belt pretensioner (LH).
3) Connect the connector (1N) in the test har-
ness N to the connector (AB21).
4) Connect the airbag resistor to the connector
(2N) of test harness N.
5) Connect the battery ground terminal and
turn the ignition switch to ON.

Does the airbag warning light
illuminate for 6 seconds and go
off?

Replace the seat
belt pretensioner
(LH). <Ref. to SB-
18, Front Seat
Belt.>

Go to step

AB-02461

1 2 3 4 5

6 7 8 9 10

11 12 13 14 15

1 2

AB17

AB21

AB17

AIRBAG CM

PRETENSIONER LH

AB(diag)-104

Diagnostic Chart with Trouble Code

AIRBAG SYSTEM (DIAGNOSTICS)

CHECK AIRBAG REAR HARNESS (PRE-
TENSIONER HARNESS LH).
1) Turn the ignition switch to OFF, disconnect
the battery ground cable, and wait for 60 sec-
onds or more.
2) Disconnect the airbag resistor from the con-
nector (2N) of test harness N.
3) Disconnect connector (AB19) from side air-
bag module (LH).
4) Disconnect the connector (AB31) from cur-
tain airbag module (LH).
5) Disconnect the connectors (AB6, AB17,
AB18) from airbag control module.
6) Connect the connector (1AH) in the test har-
ness AH to the connectors (AB6, AB17, AB18).
7) Connect the connector (2AH) in the test har-
ness AH and the connector (1AG) in the test
harness AG.
8) Measure the resistance between connector
(3AG) terminals in test harness AG.

Connector & terminal

(3AG) No. 10 — (3AG) No. 12:

Is the resistance 1 MΩ or
more?

Go to step

Replace the airbag
rear harness along
with body harness.

CHECK AIRBAG CONTROL MODULE.
1) Connect all connectors.
2) Clear the memory.
3) Perform the Inspection Mode.
4) Read the DTC.

Is the same DTC displayed?

Replace the airbag
control module.
<Ref. to AB-21,
Airbag Control
Module.>

Go to step

CHECK FOR ANY OTHER DTC ON DISPLAY. Is any other DTC displayed?

Check DTC using
“List of Diagnostic
Trouble Code
(DTC)”. <Ref. to
AB(diag)-39, List
of Diagnostic Trou-
ble Code (DTC).>

Finish the diagno-
sis.

Step

Check

Yes

AB(diag)-105

Diagnostic Chart with Trouble Code

AIRBAG SYSTEM (DIAGNOSTICS)

AW:DTC 6D BELT PRETENSIONER RH FAILURE

DTC DETECTING CONDITION:

• Seat belt pretensioner (RH) circuit is open.

• Pretensioner (RH) is faulty.

• Pretensioner harness (RH) is faulty.

• Airbag control module is faulty.
CAUTION:

• Before diagnosing the airbag system, be sure to turn the ignition switch to OFF, disconnect the

ground cable from battery, and wait 60 seconds or more before starting to work.

• When replacing the airbag module, seat belt pretensioner, roll connector, control module and sen-

sor, reconnect each part and check that the airbag warning light operates properly.

• When inspecting the airbag main harness, disconnect the airbag module connectors of the driver’s

and passenger’s seats for safety.

• When inspecting the airbag rear harness, disconnect the side airbag module connector, curtain

airbag module connector and seat belt pretensioner connector for safety reasons.

WIRING DIAGRAM:

Airbag system <Ref. to WI-82, WIRING DIAGRAM, Airbag System.>

Step

Check

Yes

CHECK POOR CONTACT OF CONNEC-
TORS.
Check for poor contact of the connectors
between the airbag control module and the seat
belt pretensioner RH.

Is there poor contact?

Replace the airbag
rear harness along
with body harness.

Go to step

CHECK SEAT BELT PRETENSIONER.
1) Turn the ignition switch to OFF, disconnect
the battery ground cable, and wait for 60 sec-
onds or more.
2) Disconnect the connector (AB26) from seat
belt pretensioner (RH).
3) Connect the connector (1N) in the test har-
ness N to the connector (AB26).
4) Connect the airbag resistor to the connector
(2N) of test harness N.
5) Connect the battery ground terminal and
turn the ignition switch to ON.

Does the airbag warning light
illuminate for 6 seconds and go
off?

Replace the seat
belt pretensioner
(RH). <Ref. to SB-
18, Front Seat
Belt.>

Go to step

AB-02460

AB18

1 2 3 4 5

6 7 8 9 10

11 12 13 14 15

AB26

1 2

AB26

AB18

AIRBAG CM

PRETENSIONER RH

AB(diag)-106

Diagnostic Chart with Trouble Code

AIRBAG SYSTEM (DIAGNOSTICS)

CHECK AIRBAG REAR HARNESS (PRE-
TENSIONER HARNESS RH).
1) Turn the ignition switch to OFF, disconnect
the battery ground cable, and wait for 60 sec-
onds or more.
2) Disconnect the airbag resistor from the con-
nector (2N) of test harness N.
3) Disconnect connector (AB24) from side air-
bag module (RH).
4) Disconnect the connector (AB33) from cur-
tain airbag module (RH).
5) Disconnect the connectors (AB6, AB17,
AB18) from airbag control module.
6) Connect the connector (1AH) in the test har-
ness AH to the connectors (AB6, AB17, AB18).
7) Connect the connector (2AH) in the test har-
ness AH and the connector (1AG) in the test
harness AG.
8) Measure the resistance between connector
(3AG) in the test harness AG and connector
(2N) in the test harness N.