The airbag code 27 is an easy fix. I just bought a used 2000 Ranger 4x4; after the 2nd day of ownership, the airbag light flashed the 2, then the 7 code. This is simply the bulb burned out on the circuit board of the passenger airbag disable module. it's the one where you put the ignition key in it, and turn it to disable. If the bulb burns out, the code 27 is set. To fix, you only beed to buy a 12 volt bulb from any electronics store like radio shack, and solder it onto the circuit board and your good to go.
No doubt this has been talked about here already. A simple two dollar or less fix.