What was found
FLAPS CAUTION LIGHT ON CWP ILLUMINATED DURING CRUISE. RESET BREAKER AND LIGHT WENT OUT. WHEN FLAPS SELECTED DURING APPROACH, CWP LIGHT CAME ON AND BREAKER POPPED, COMPLETED O DEGREE FLAP LANDING. RETURNED TO DTW. MAINTENANCE REPLACED FLAP CONTROL VALVE AND FLAP CONTROLLER. PERFORMED FUNCTION CHECKS OF FLAPS IAW AMM 27-51-00, ALL CHECKS GOOD.