Conditions for Running the DTC

WARNING: This page is about a different car, the 2008 Cadillac CTS. However, it is still accessible from the selected car via links, so may be relevant.

DTC P0641, P0642, or P0643 is not set.
The ignition voltage is between 6-18 volts.
DTCs P0090, P0091, and P0092 run continuously.