Theory Of Operation
WARNING: This page is about a different car, the 2017 RAM 2500 HD. However, it is still accessible from the selected car via links, so may be relevant.
The purpose of the diagnostic is to check the PTO relay enable circuit for open or short to voltage conditions. The PTO relay enable circuit is powered by a high side driver in the PCM. If the feedback circuit voltage is high while the in cab PTO switch is turned off, this DTC will be set once the in cab PTO switch is turned on. The PTO will disengage when this condition is present.