Normal Operation - Automatic Transaxle
WARNING: This page is about a different car, the 2009 Mercury Milan, 2009 Lincoln MKZ, and 2009 Ford Fusion. However, it is still accessible from the selected car via links, so may be relevant.
When the transaxle is placed in REVERSE (R), the transmission control module (TCM) sends gear status information (through the instrument cluster [IC] gateway) to the smart junction box (SJB). When the SJB receives a message indicating the transaxle is in REVERSE (R), the SJB provides ground to an internal relay, which routes the voltage to circuit CBP12 (GN/WH) to the reversing lamps and the electrochromatic rear view mirror (if equipped).