There's a calibration for wheel angle sensor and steering spool stored on the tractor.  I've seen where the AgLeader system will not show good CAN communication because there is a bad wheel angle sensor or a bad calibration for the wheel angle sensor stored on the valve.

The Wheel angle sensor and the SASA sensor are the two inputs to the PVED valve.  If one or both (usually one) of them is not reading correctly, it throws a fault code and the PVED valve goes into safety mode. However on the RT A series that fault doesn't display on the dash.  Only way to tell is by hooking up an AGCO EDT box.

I know this explanation doesn't add up if it had a Trimble System on it previously but I do know this can be a snag for what you're trying to accomplish.