Pinpoint Test AG: DTC U0155 Or DTC U0155:00: Notes
WARNING: This page is about a different car, the 2011 Mercury Milan, 2011 Lincoln MKZ, and 2011 Ford Fusion. However, it is still accessible from the selected car via links, so may be relevant.
Refer to SYSTEM WIRING DIAGRAMS article, Audio System/Navigation for schematic and connector information.