Electronic Throttle Control (ETC)
WARNING: This page is about a different car, the 2006 Ford F550 Super Duty, 2006 Ford F450 Super Duty, and 2006 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.
The instrument cluster receives the ETC status from the PCM over the communication network. When a system concern is detected, the PCM sends the instrument cluster a command signal to illuminate the ETC indicator.