AIRBAG SYSTEM (DIAGNOSTICS) > Diagnostic Chart with Trouble Code

DTC F4 SIDE SENSOR BUS LH COMMUNICATION ERROR

DTC DETECTING CONDITION:

• Open or short circuit in harness of side sensor bus (LH).

• Side airbag sensor (LH) and curtain airbag sensor (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 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 warning light operates properly.

• When inspecting the airbag main harness, disconnect the airbag module connectors and seat belt pretensioners of the driver’s and passenger’s seats for safety reasons.

• 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 (AB17, AB23, AB32) between the airbag control module and the curtain airbag sensor (LH).

Is there poor contact?

Replace the airbag rear harness along with body harness.

2.CHECK AIRBAG REAR HARNESS (BETWEEN AIRBAG CONTROL MODULE AND SIDE AIRBAG SENSOR LH).

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

2) Disconnect the connector (AB21) from seat belt pretensioner (LH).

3) Disconnect the connector (AB31) from curtain airbag module (LH).

4) Disconnect connectors (AB19) and (AB20) from side airbag module (LH).

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

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

7) Disconnect the connector (AB23) from side airbag sensor (LH), and connect the connector (2V) in test harness V to connector (AB23).

8) Measure the resistance between connector (5AG) in the test harness AG and connector (3V) in the test harness V.

Connector & terminal

(5AG) No. 10 — (3V) No. 1:

(5AG) No. 8 — (3V) No. 2:

Is the resistance less than 10 Ω?

Replace the airbag rear harness along with body harness.

3.CHECK AIRBAG REAR HARNESS (BETWEEN AIRBAG CONTROL MODULE AND SIDE AIRBAG SENSOR LH).

Measure the resistance between connector (5AG) in the test harness AG and chassis ground, and the resistance between connector (5AG) terminals in the test harness AG.

Connector & terminal

(5AG) No. 10 — Chassis ground:

(5AG) No. 8 — Chassis ground:

(5AG) No. 10 — (5AG) No. 8:

Is the resistance 1 MΩ or more?

Replace the airbag rear harness along with body harness.

4.CHECK AIRBAG REAR HARNESS (BETWEEN SIDE AIRBAG SENSOR LH AND CURTAIN AIRBAG SENSOR LH).

1) Disconnect the connector (2V) in the test harness V from the connector (AB23) of side airbag sensor (LH).

2) Connect the connector (AB23) of side airbag sensor (LH) and the connector (1AI) in the test harness AI.

3) Connect the connector (2AI) in the test harness AI and the connector (1V) in the test harness V.

4) Disconnect the connector (AB32) from curtain airbag sensor (LH), and connect the connector (2V) in test harness V to connector (AB32).

5) Measure the resistance between connector (3V) terminals in the test harness V.

Connector & terminal

(3V) No. 2 — (3V) No. 6:

(3V) No. 1 — (3V) No. 7:

Is the resistance less than 10 Ω?

Replace the airbag rear harness along with body harness.

5.CHECK AIRBAG REAR HARNESS (BETWEEN SIDE AIRBAG SENSOR LH AND CURTAIN AIRBAG SENSOR LH).

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

Connector & terminal

(3V) No. 2 — Chassis ground:

(3V) No. 1 — Chassis ground:

(3V) No. 2 — (3V) No. 1:

Is the resistance 1 MΩ or more?

Replace the airbag rear harness along with body harness.

6.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?

7.REPLACE SIDE AIRBAG SENSOR (LH) AND CHECK AIRBAG CONTROL MODULE AFTER REPLACEMENT.

1) Connect all connectors.

2) Erase the memory.

3) Perform the Inspection Mode.

4) Read the DTC.

Is the system normal?

Replace the curtain airbag sensor (LH). Replace the airbag control module if not operating normally even after replacing the sensor.

8.CHECK FOR ANY OTHER DTC ON DISPLAY.

Is any other DTC displayed?

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

Finish the diagnosis.