Ford has an issue with some of these cars where the wiring harness under the front seats and positioned in the wrong way, so that when you move the seat the wires get pinched by the seat, breaking them. A complete harness is more than likely to fix the issue, and the issue will get progressively worse (light appearing more often). This may cause your side airbags not to deploy in a crash. Dealer refuses to replace the wiring harness without diagnostics testing.

Update from Jan 28, 2016: This issue ended up being that the wires inside of the yellow wiring connector under the seat that had broken. These wires were removed and heatshrink wrapped into place from another wiring connector. Fix is roughly $20 if you can find a good harness and know how to splice wires