Camshaft Positioning Sensor 1998 Windstar

I am having trouble with the CMP P0340 code. I need to track down the ground wire to check its connection. Can anyone tell me where ther ground wire is loacted? Is it attached to the PCM? I am trying to sell the windstar.
The check engine light came on during the trest drive. Kinda blew the deal. I have a reader and am getting p0340 circuit malfunction. Help!!
Or by the windstar for $4999. 65k miles.

Did you get a reply? I am having the same problem.