Sensor, PTO Switch: 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.
This input is used only to tell the Powertrain Control Module (PCM) that the aftermarket PTO (Power Take Off) unit has been engaged. The PCM will disable (temporarily shut down) certain OBD II diagnostic trouble codes when the PTO unit is engaged.