Answer Hello Art. If a Central Control Unit Heartbeat Failure is displayed,no communication is detected from the Central ControlUnit (CCU) to the User Interface. 1. Check for continuity of the User Interface harness.2. Check wire harness connections to the User Interfaceand Central Control Unit.3. If the drum is not rotating, unplug the MCU from theCCU (the MI3 or M13 connector). If the code goesaway, then replace the MCU. If the code does not goaway, replace the CCU.4. Replace User Interface if drum is rotating. Read More... Safety note: testing, adjusting or bypassing anything while the appliance has power is a job for a qualified technician. Unplug it before you open it up, and keep it unplugged until every panel is back on. Answered by AppliancePartsPros.com | Tuesday, September 17, 2013