Look down through the fan and to the right (below the water pump). You will see the sensor attached to a bracket above the damper pulley. It will have a lead attached to it. That's your sensor. However, and I could be wrong, if that item isn't working, your motor would not start, or if it did, your ECM wouldn't be getting good info for spark advance, etc.
2000 Dodge Grand Caravan SE
No matter what you fix, there will always be something else to fix..
"Warranty" is just another way of postponing the inevitable.