Conditions for Running the DTC

WARNING: This page is about a different car, the 2007 Hummer H2. However, it is still accessible from the selected car via links, so may be relevant.

DTCs P0601, P0602, P0604, P0606, P1516, P2101, P2108, U0107 are not set.
DTCs P0120 and P0220 are not active at the same time.
The engine operates longer than 1 second.
The engine speed is more than 500 RPM.
DTC P0068 runs continuously once the above conditions are met.