Normal Operation
WARNING: This page is about a different car, the 2005 Lincoln LS. However, it is still accessible from the selected car via links, so may be relevant.
The passenger rear heated seat module is powered by battery voltage on circuit 30-HC21 (RD/GN) and by ignition voltage circuit 20-HC21D (PK/YE), and is supplied ground on circuit 31-HC21 (BK/GN). The heated seat switch has a high and low setting depending on selection. The heated seat switch uses the ground on circuit 31-HC18 (BK/GN) to provide a ground input to the heated seat module on circuit 8-HC21A (WH/GN) (high setting) or 10-HC21A (GY/OG) (low setting). The heated seat module supplies voltage to the heated seat elements in the seat cushion and the seat back.