Question about a 2000 Plymouth Voyager?

Yesterday when I was driving the van the speedometer quit working and it wont shift. A guy told me it was my Turbine output speed sensor located on the left side of the van on the front of the Transmission a little bit towards the top. It is a plastic piece with a plug comming from it. It has a 24 MM Hex head Just want to know if I have it right.