Conditions for Setting the DTC: P0602
WARNING: This page is about a different car, the 2009 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.
The ECM has not been programmed with Key ON and Engine OFF for one sample. Each sample is 100 milliseconds. The ECM has not been programmed at Key ON and Engine OFF for 0.1 second. This diagnostic runs continuous.