The ground path goes from C227 though C202 Pin 63 to G100 located on the LH front of engine compartment, on upper radiator support. There is no sensor in the path unless ground G100 attachment is bad. You may need to trace it from end-to-end (I would take a look at G100 first to see if the attachment may be corroded of loose). See the attached for more info. Cheers!