AIRBAG SYSTEM (DIAGNOSTICS) > Diagnostic Chart with Trouble Code

DTC 81 LAP SEAT BELT PRETENSIONER FAILURE

DTC DETECTING CONDITION:

• Lap seat belt pretensioner (RH) circuit is open, shorted or shorted to ground.

• Lap seat belt pretensioner is faulty.

• Lap seat belt pretensioner harness 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 terminal from the battery, and wait 20 seconds or more before starting to work.

• When replacing the airbag module, seat belt pretensioner, lap seat belt pretensioner, roll connector, control module and sensor, 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, seat belt pretensioner and lap seat belt pretensioner connector for safety reasons.

WIRING DIAGRAM:

STEPCHECKYESNO

1.CHECK POOR CONTACT OF CONNECTORS.

Check for poor contact of the connectors between the airbag control module and the lap seat belt pretensioner.

Is there poor contact?

Replace the airbag rear harness along with body harness.

2.CHECK LAP SEAT BELT PRETENSIONER.

1) Turn the ignition switch to OFF, disconnect the battery ground cable, and wait for 20 seconds or more.

2) Disconnect the connector (AB30) from lap seat belt pretensioner (RH).

3) Connect the connector (1Q) in the test harness Q to connector (AB30).

4) Connect the airbag resistor to the connector (2Q) in the test harness Q.

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 lap seat belt pretensioner (RH).

3.CHECK AIRBAG REAR HARNESS (SIDE AIRBAG HARNESS RH).

1) Turn the ignition switch to OFF, disconnect the battery ground cable, and wait for 20 seconds or more.

2) Disconnect the airbag resistor from test harness.

3) Disconnect the connector (AB33) from curtain airbag module (RH).

4) Disconnect connector (AB24) from side airbag module (RH).

5) Disconnect the connector (AB26) from seat belt pretensioner.

6) Disconnect the connectors (AB6, AB17, and AB18) from the airbag control module.

7) Connect the test harness AG connector (1AG) to the connectors (AB6, AB17, and AB18).

8) Measure the resistance between the test harness AG connector (3AG) and the test harness Q connector (2Q).

Connector & terminal

(3AG) No. 19 — (2Q) No. 1:

(3AG) No. 17 — (2Q) No. 2:

Is the resistance less than 10 Ω?

Replace the airbag rear harness along with body harness.

4.CHECK AIRBAG REAR HARNESS.

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

Connector & terminal

(3AG) No. 17 — (3AG) No. 19:

(3AG) No. 17 — Chassis ground:

(3AG) No. 19 — Chassis ground:

Is the resistance 1 MΩ or more?

Replace the airbag rear harness along with body harness.

5.CHECK AIRBAG CONTROL MODULE.

1) Connect all connectors.

2) Erase the memory.

3) Perform the Inspection Mode.

4) Read the DTC.

Is the same DTC displayed?

Replace the airbag control module.

6.CHECK FOR ANY OTHER DTC ON DISPLAY.

Is any other DTC displayed?

Check DTC using “List of Diagnostic Trouble Code (DTC)”.

Finish the diagnosis.