Principles of Operation
WARNING: This page is about a different car, the 2007 Lincoln Mark LT and 2007 Ford Pickup. However, it is still accessible from the selected car via links, so may be relevant.
For vehicles equipped with an automatic transmission, the digital transmission range (TR) sensor routes voltage to the reversing lamps when the transmission is placed in REVERSE (R).
For vehicles equipped with a manual transmission, the reversing lamp switch routes voltage to the reversing lamps when the transmission is placed in REVERSE (R).