Normal Operation
WARNING: This page is about a different car, the 2006 Mercury Grand Marquis and 2006 Ford Crown Victoria. However, it is still accessible from the selected car via links, so may be relevant.
The battery junction box (BJB) supplies voltage to the stoplamp switch through circuit 1119 (RD). When the brake pedal is applied, the stoplamp switch routes voltage to the stoplamps through circuit 10 (LG/RD).