Why did our Peugeot 406's airbag deploy for no reason?

I was driving my wife’s 1999 Peugeot 406 110 HDI estate earlier today when the airbag warning light came on. The car has been prone to a few electrical faults in the past, so I thought I would take the car to the dealers on Monday. Three hours later, as we both were in the car, the passenger airbag deployed without reason, luckily at a slow speed. How common is this, and should Peugeot be contacted?

Asked on 16 June 2012 by MG, via email

Answered by Honest John
This is a car built to last 6-7 years that has lasted 13 years. Airbags suddenly going off in old cars is not actually very common, but all airbag warning lights are now subject to the MoT test and a car will fail if the lights show anything wrong. If the problem isn’t something simple like an external cable or connector, it will make many cars like yours economic write-offs. www.airbagman.co.uk may be able to help.
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