Switch - PTO: Operation
WARNING: This page is about a different car, the 2005 Dodge Pickup and 2005 Dodge Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.
This input is used only to tell the ECM that the aftermarket PTO (Power Take Off) unit has been engaged. The ECM will disable (temporarily shut down) certain OBD II diagnostic trouble codes when the PTO unit is engaged.