1. A rail vehicle, comprising: a wagon body and a suspension system comprising a running gear supporting said wagon body wherein a sensor device and a control device are provided; said sensor device capturing an actual value of at least one status variable, said status variable being representative of a spatial relationship between a first reference part of said sensor device associated to a part of said running gear and a second reference part of said sensor device associated to said wagon body; said control device performing a malfunction analysis using said actual value of said status variable, said malfunction analysis assessing fulfillment of at least one predetermined malfunction criterion; and said control device providing a malfunction signal if said malfunction analysis reveals that said malfunction criterion is fulfilled.