All error codes By model: T1100T1500T1600T1700T2300T2500T2600T610T730T830T930Z5200Z6Z6200Z9 Model T1600 Error Code 0090-0018-0004 Problem Description Unable to connect to front panel or Control panel connection lost Corrective Action Options Upgrade the firmware to the latest version. Schedule Service Call ⭢ (301) 340-0000 Email ⭢ Contact Us