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 2008 Mercury Sable, 2008 Ford Taurus X, and 2008 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.