Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 315
Aircraft Equipment Problem Critical
Flight Crew Overcame Equipment Problem
Aircraft
While on the arrival and in IMC; we encountered an MCP lockup.  The autopilot kicked off and the MCP went to 888's.  We could not silence the Altitude Alert.  I took the controls and flew the plan manually and released the HGS combiner.  I leveled off using the HGS.  I told the First Officer to pull out the QRH and run the MCP Lockup checklist.  The First Officer reset four CB's and the MCP restored itself.  Flight returned to normal.
B737 Captain experiences a MCP lockup during arrival resulting in autopilot disconnect and a continuous altitude alert.  The Captain takes control and levels the aircraft while the First Officer preforms the QRH procedure and restores the MCP to normal operation.