B737 Undifferentiated or Other Model
Flight Crew Last 90 Days 226
Confusion
Aircraft Equipment Problem Critical
Flight Crew Returned To Departure Airport; General Declared Emergency
Aircraft
During climbout at approximately 5;000 feet ATC queried us to reset our transponder.  I reset the transponder and at that time the Captain's display units started to fail.  Next the First Officer's display units started to fail.  The Captain continued to fly as I got out the QRH.  Passing through 13;000 feet we asked ATC to level off so we could evaluate the situation.  I read the QRH checklist to determine which checklist applied.  I looked at the Display Failure Checklist first and that did not seem to apply.  I next checked the Displays Control Panel Checklist and then the Display Source Checklist and neither seemed to apply. There were no yellow or red lights on the overhead panel; glare shield or instrument panel that would give an indication of which checklist to use. The Captain declared an emergency and we received vectors back.  The Captain was flying with his standby instruments.  We had no airspeed; altitude; autopilot; or FMA on our primary display.  SPD and ALT and TCAS fail were displayed on the PFD.  In addition; the MCP was not working; none of the buttons were lit; and we could not select VNAV; LNAV or heading select.  The autopilots would not engage.  Further; there did not appear to be any circuit breakers popped. I briefed the flight attendants that we had a system failure and we would be returning and to prepare the cabin for a normal landing.  I then briefed the passengers that we had a system failure and would be returning for a normal landing.  ATC continued to give us vectors to return to the airport and I began to program the FMC for the approach and tune the radios.  We were in and out of IMC conditions; finally we were able to see the field and we were cleared for a visual approach.  During the approach some of the First Officer instruments returned.  The Captain made a normal approach and landing using his standby instruments.
Before takeoff; we both had a TCAS fail. At 7;000 feet ATC lost our transponder and we had a fail light on the transponder. At 13;000 feet Captain and First Officer's instruments each lost all the numbered information on PFD's and ND's. The MCP lost all functions. We declared an emergency; accomplished checklists and returned.
B737 flight crew reports loss of all number information on their PFD's and ND's along with MCP failure during initial climb. An emergency is declared and the flight returns to the departure airport.