Conditions for Setting the DTC (W/O F55)

WARNING: This page is about a different car, the 2009 Cadillac DTS. However, it is still accessible from the selected car via links, so may be relevant.

The exhaust solenoid control circuit is shorted to voltage, ground, or open when solenoid activation is commanded ON for 2.5 seconds.
The exhaust solenoid B+ circuit is shorted to ground or open when solenoid activation is commanded ON for 5 seconds.