Pinpoint Test F: DTC C1742 and C1743 - Rear Sounder Circuit Short To Vbatt & Rear Sounder Circuit Failure: Notes
WARNING: This page is about a different car, the 2009 Mercury Sable, 2009 Ford Taurus X, and 2009 Ford Taurus. However, it is still accessible from the selected car via links, so may be relevant.
Refer to appropriate SYSTEM WIRING DIAGRAMS article, Parking Aid for schematic and connector information.