2014 Grand C4 Airbag Fault

[spagy86]

Hi all - error showing on screen for airbag/pretensioner fault. Happens intermittently multiple times. Seems to happen if I lean forward in the driver's seat.

Diagbox showing an earth fault on the drivers airbag, which is confusing considering me moving in the seat affects it.

Any ideas on the wiring locations and where I should check?

Many thanks!

[GiveMeABreak]

The driver airbag is obviously in the steering wheel boss, so it may be referring to the side airbag in the driver seat. Do you have the actual fault code(s) reported by Diagbox and the VIN (please post your VIN in full without spaces - it will be automatically masked from public view after submitting your post & will only be visible to staff).

[spagy86]

I'll plug in again and get back to you with the fault code. I know from a battery test a few months ago that it is weak, so also wonder if this could be the cause.

[GiveMeABreak]

A weak battery can certainly cause electrical problems - anything over 5 years old and is probably due a replacement, especially with Stop / Start and the amount of electrical equipment on board. If the ECUs are under voltage it can cause faults to be triggered. It may well be a wire that has work causing a short or intermittent operation, but the code may give a clue.

[spagy86]

The code is B0028 11. Front right side airbag line fault. What should I be checking?

[GiveMeABreak]

So as I thought it is the side airbag / connection that is triggering a fault. It may be that the harness or a wire has become kinked or is partially worn through. It will need testing with proper equipment given the dangers involved, so I'd get it looked at by a dealer or other professional.

Fault Code:	B0028 11
Description of Fault:	Front right side air bag line fault: Short circuit to earth. A part of the line is in short-circuit with the earth for more than 2 seconds. Thje fault is triggered if the following conditions are met: - Ignition switched on - Absence of a fault which inhibits all of the ignition modules - Air bags and pretensioners ECU not locked after an accident (it is possible to clear the faults)
Conditions for Fault to clear:	More than 2 seconds without short-circuit of the line with the earth Display of the air bags and pre-tensioners fault warning lamp / symbol
Downgrade Modes whilst Fault is active:	Recording of the fault in the built-in systems interface (BSI) faults log (JDD)
Symptoms:	Display of the air bags and pre-tensioners fault warning lamp / symbol
Suspect Areas:	Front right side air bag Seat harness Cabin harness Connectors Airbags and pretensioners control unit

Warning: Risk of pyrotechnic deployment, do not perform any measuring on the pyrotechnic line.