Speed Control Indicator
WARNING: This page is about a different car, the 2005 Ford Pickup, 2005 Ford F550 Super Duty, 2005 Ford F450 Super Duty, and 2005 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.
The instrument cluster receives the speed control signal from the PCM over the communication network. The PCM communicates to the instrument cluster to illuminate the speed control indicator when the speed control is engaged.