What was found
(CAN) AFTER TAKEOFF, THE FLAPS STOPPED AT 4 DEGREES. THE FLAP PWR CAUTION LIGHT CAME ON. CLIMBED TO 300 FT ON A HEADING OF 120 AND CALLED FOR THE CHECK LIST. UPON COMPLETION OF CHECK LIST THE CAUTION LIGHT REMAINED ON, AT THIS TIME ASKED FOR A TURN. FOLLOWED SOP`S AND EMERGENCY CHECK LIST TO A (T). DECLARED AN EMERGENCY AND LANDED ON RUNWAY 05. THE LANDING WAS UNEVENTFUL AND TAXIED CLEAR OF THE RUNWAY AT FOXTROT. EMERGENCY VEHICLES GAVE THE ALL CLEAR AND SINCE BRAKE COOLING WAS NOT A FACTOR, TAXIED TO LANDMARK. FLAP CONTROL UNIT CONTINUOUS BIT FAULT IN CSD. FIM TASK 27-50-00-810-807 COMPLETE. FAULT DID NOT RE-OCCUR AFTER FUNCTIONAL TEST.