Airbag ECU - flashing airbag light

November 23, 2018

Guys, I just wanted to post this up for future reference.

About 3 weeks ago, on starting the car my airbag light started flashing. It has never done so before and I can think of no reason as to why it should come on out of the blue. I checked the usual suspects (around the underseat airbag connectors) which were fine, and the resistor fuses had not moved since I removed the factory airbag seats years ago. I also checked the connections on the airbag ECU (removed and refitted) as well as the side impact sensor plug. Also removed and refitted the passenger and drivers airbag plugs. Obviously the Battery had also been disconnected during all this for a total of at least an hour. The Battery itself was new this year as well.

Powered it all back up - no change. I hadn't considered the ECU itself could be at fault - after all there are no moving parts and its well bolted down so I suspected either the driver or passenger dash airbags had become faulty.

With nothing else left for me to try at home, I contacted my local garage who confirmed they had all the correct kit to read, diagnose and clear airbag codes at £54 inc vat.

Just before booking it in I thought I would have another scour of the web and found a few people who had had the same problem with Aygos/107's and that it had been diagnosed to faulty airbag ECU's, a couple being replaced under warranty and another one costing £240 outside of warranty.

I took a very large gamble and thought I would give it a go. I found a secondhand ECU on the bay with the seller confirming that no codes were stored. £40 delivered. Just fitted it all up and bingo - airbag light comes on as usual with ignition on then goes off after a few seconds as it should. Very happy.

Just something to bear in mind if you get a flashing airbag light and have checked all the connections. It appears that the ECU's can and do go pop for no apparant reason whatsoever.

November 24, 2018

Thanks for posting, always helpful to hear other peeps success stories. I have heard a few people who had airbag issues related to underseat connectors and clock spring, but not heard the ECU one before, but I have now, so thanks again.