Action Taken When the DTC Sets

WARNING: This page is about a different car, the 2003 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.

The ECM illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
The ECM disables Cruise Control.
The ECM records the operating conditions at the time when the Conditions for Setting the DTC are met. The ECM stores this information as Freeze Frame and Failure Records.
The ECM stores P0502 in PCM history.