SAAB WIS ONLINE

DTC 31

DTC 31

DTC DTTECTING CONDITION:


Front sub sensor harness (RH) circuit is shorted.

Front sub sensor harness (RH) circuit is open.

Front sub sensor (RH) is faulty.

Airbag control module is faulty.


Important
Before diagnosing the airbag system, be sure to turn the ignition switch to OFF, disconnect the ground cable from battery, and wait more than 20 seconds before starting to work.

Before replacing the airbag module, seat belt pretensioner roll connector, control module, and sensor, reconnect each part and confirm that the warning light operates properly.

When inspecting the airbag main harness, disconnect the driver’s airbag module and passenger’s airbag module connectors for safety reasons.


WIRING DIAGRAM:


CHECK FRONT SUB SENSOR (RH) AND FRONT SUB SENSOR HARNESS (RH).

Turn the ignition switch to OFF, disconnect the battery ground cable, and wait more than 20 seconds.

Disconnect the connector (AB3) from the airbag control module, and connect the connector (1R) in test harness R.

Measure the resistance of the connector (3R) in test harness R.

Connector & terminal

(3R) No. 7 — (3R) No. 9:

Is the resistance 750 Ω — 1 kΩ?

Yes

Replace the airbag control module.


No


CHECK FRONT SUB SENSOR (RH) AND FRONT SUB SENSOR HARNESS (RH).

Measure the resistance between connector (3R) in test harness R and the chassis ground.

Connector & terminal

(3R) No. 7 — Chassis ground:

(3R) No. 9 — Chassis ground:

Is the resistance more than 1 MΩ?

Yes

Replace the airbag control module.


No


CHECK AIRBAG MAIN HARNESS AND FRONT SUB SENSOR HARNESS (RH).

Disconnect the connector (AB15) from the front sub sensor.

Connect the connector (1H) in test harness H to connector (AB15).

Measure the resistance between connector (3R) in test harness R and connector (3H) in test harness H.

Connector & terminal

(3R) No. 7 — (3H) No. 6:

(3R) No. 9 — (3H) No. 5:

Is the resistance less than 10 Ω?

Yes


No

Replace the body harness with airbag main harness.


CHECK AIRBAG MAIN HARNESS AND FRONT SUB SENSOR HARNESS (RH).

Measure the resistance between connector (3R) in test harness R and the chassis ground.

Connector & terminal

(3R) No. 7 — Chassis ground:

(3R) No. 9 — Chassis ground:

Is the resistance more than 1 MΩ?

Yes

Finish the diagnosis.


No

Replace the front sub sensor (RH).