Hello Gail
When your son ran in to the ditch it is very likely that something in the belt configuration got slightly bent. Just a small bend in the wrong direction will misguide the belt, which will result in the problem you are having. The mechanic should examine this configuration very carefully and see where the weakest point is, that would be the area to look at. Example being, tension pulley or attaching bracket. If you continue to have this problem, contact an authorized Chrysler dealer and consult with the service advisor. They sometimes know where the weak point is.
Dan
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