F00F - Control unit not transmitting on the CAN network airbag control unit fault

What does error code F00F mean in the airbag control unit?

Error code F00F reports that the airbag control unit is no longer transmitting on the vehicle's CAN network, that is, a fault in its communication on the vehicle network. The control unit itself is affected, that is, the central unit of the restraint system (SRS) that triggers the airbags and seatbelt pretensioners in an accident.

The control unit stores the fault in the fault memory and switches on the airbag warning light. The warning light thus shows the driver that there is a fault in the restraint system.

How do you recognise error code F00F?

You recognise error code F00F by the airbag warning light staying on permanently and the code being stored in the fault memory of the airbag control unit. It cannot be permanently erased from the fault memory, and the airbag warning light does not go out on its own; it stays on until the fault has been resolved.

Have the code read out with a diagnostic tool, which displays the entry from the control unit's fault memory.

What causes error code F00F?

Error code F00F occurs when the control unit stops transmitting on the CAN network and communication with it is interrupted. The possible causes are the control unit itself, the power supply, and the data line with its connectors and contacts, although the cause can only be narrowed down during testing.

• The control unit itself is faulty, so it no longer transmits on the network.
• The power supply to the control unit is weak or interrupted.
• The data line in the CAN network is damaged.
• Connectors on the data line are loose, dirty or corroded.

Which of these parts is affected can only be established by a detailed check in each individual case.

In which vehicles does error code F00F occur?

Error code F00F is known in Citroën vehicles, namely in the models C3 Aircross III, C3 Picasso I, C4 Aircross I, C4 Cactus I, C5 Aircross II and ë-C3 IV. The list is not complete, because not every vehicle that can show the code has been recorded.

On other vehicles, the meaning of the code may differ from that described here. Whether your vehicle is affected can therefore only be checked case by case.

How is error code F00F resolved?

Error code F00F is resolved by first having the fault memory read out with a diagnostic tool and then having the cause checked at a specialist workshop. If the cause lies in the control unit itself, it is removed after the battery has been disconnected and sent to Airbag24 for repair.

First have the fault memory read out with a diagnostic tool. If connectors, wiring or the power supply come into question as the cause, have these checked at a specialist workshop first.

If the cause lies in the control unit itself, the battery is disconnected first, and only then is the control unit removed. Then create a repair order online and send the unit to Airbag24. Checking, repairing and testing usually take 3–4 working days. The repaired control unit comes back with all vehicle data and is ready for use as soon as it is refitted — no coding or programming is required.

Work on the airbag system should be left to qualified specialists.