Conditions for Setting the DTC: P0606
WARNING: This page is about a different car, the 2009 Pontiac Torrent and 2009 Chevrolet Equinox. However, it is still accessible from the selected car via links, so may be relevant.
The ECM detects an internal error of the monitoring software for the throttle actuator control (TAC) system. The condition exists, then a 5 second delay for MIL ON.