1994 Dodge Truck alternator charging

My truck that I just got has a engine service light on but 2 days in driving it seems to have no noticable effect on truck, however when coming home from work yesterday I noticed voltage was down around 10amps. I was getting close to home when it suddenly dropped to 0 I got it in drivway and shut it off. Went out 30 min later it fired right up and was charging normal. Could it be ignition switch? The truck was in a front end collision and the air bag were deployed and it appears they glued it back together and air bag light is on also the fuel gauge doe not work. Thanks for any direction you can point me in. Jeff