When I worked on my alternator, I pulled my passenger-side seat (including disconnecting the wiring harness). I can't remember absolutely, but I'm pretty sure I disconnected the battery first. I still got an airbag CEL. (Which created a really irritating situation for me: I spent as much at the stealership to get the CEL cleared as I did having the alternator rebuilt. IT DOUBLED THE COST OF MY PROJECT!
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