If the vehicle is upgrading to a Sync 4 and also is replacing the ACM for the X65 to retain Sirius XM and gain Mix Modes, and the Satellite Radio is giving a Hardware Error message, then there's an issue with a connection.
Please ensure the Satellite Antenna is fully seated to the ACM (Curry/Yellow antenna connector on radio unit) and make sure that the APIM harness and ACM harness are connected with the "A" Connector together.
A satellite hardware error is never an issue with the ACM itself, it's always going to be a harness or a connection issue. Especially if AM/FM work fine.