Why is it so expensive to replace my BMW 335's faulty airbag warning switch?

For about a year I have had an airbag warning light showing on my 2006 BMW 335ci which has covered a mere 15,000 miles. Last week I had it booked in to the local BMW dealer and received a severe shock when the bill to replace the defective switch, which is fitted into the steering wheel hub, came to £521.90. Does this seem reasonable to you and can a switch really cost £355.84? The car has never been in an accident or had anything occur that could have caused this breakdown.

Asked on 28 April 2012 by CB, North Somerset

Answered by Honest John
That's the sort of bill a lot of drivers face now that an airbag warning light is an MoT failure. Better to use a specialist such as www.airbagman.co.uk.
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