The contact owns a 2013 Lincoln MKS. The contact stated that while operating the vehicle, the defroster setting malfunctioned, and the contact was unable to defrost and clear the windows, creating a visibility hazard. The vehicle was taken to the local dealer who diagnosed that the Accessory Protocol Interface Module (APIM) was faulty and needed to be replaced. The vehicle was not yet repaired. The manufacturer was notified of the failure, but no assistance was offered. The failure mileage was 157,000.