What was found
WHILE RETRACTING FLAPS AFTER TAKEOFF THE INBOARD FLAPS STOP RETRACTING AT APPROXIMATELY 12 DEGREES, WHILE THE OUTBOARD AND NACELLE FLAPS STOP AT APPROXIMATELY 6 DEGREES. PERFORMED QRH PROCEDURE FOR A FLAP DISAGREEMENT. THE PROBLEM DID NOT CORRECT ITSELF. RETURNED TO LAX FOR LANDING. ENABLED MX MODE OF ANN PNL. ALL HISTORIES REPORTED NO FAILURES. CLEANED ALL CANNON PLUGS. RESTORED A/C TO NORMAL. CYCLED FLAPS 50+ TIMES. NO DISCREPANCIES NOTED.