Pinpoint Test C: DTC P0579 or P0581 - Speed Control Switch Circuit Failure: Notes
WARNING: This page is about a different car, the 2008 Mercury Milan, 2008 Lincoln MKZ, and 2008 Ford Fusion. However, it is still accessible from the selected car via links, so may be relevant.
Refer to SYSTEM WIRING DIAGRAMS article for Fusion, SYSTEM WIRING DIAGRAMS article for Milan or SYSTEM WIRING DIAGRAMS article for MKZ, Speed Control for schematic and connector information.