The first thing to do is disconnect your battery if you are fiddling about with airbags, the seat belt pre tensioner wiring is usually located under the front seats and there should be a couple of connectors for passenger and driver side seat belts,a high resistance sometimes builds up at these connectors and by disconnecting and reconnecting usually sorts out the problem, sometimes the connectors are located on the actual seat belt mechanism themselves on the side panels, if not then about the only other thing to do is to get the fault diagnosed on a computer/code reader which should point you in the right direction
cdc
April 2015
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