What was found
(CAN) ON A ROUTINE FLIGHT, IT WAS OBSERVED THAT WHEN THE FLAP HANDLE WAS SELECTED TO APPROACH THE FLAPS DID NOT MOVE. THE CREW CONDUCTED A FLAPLESS LANDING WITHOUT INCIDENT. MAINTENANCE DISCOVERED THAT THE UP LIMIT SWITCH WAS FULL OF WATER A FROZEN, FURTHER INSPECTION REVEALED THE AIRCRAFT HAD JUST BEEN WASHED PRIOR TO DISPATCH. MAINTENANCE CLEANED THE SWITCHES WITH CONTACT CLEANER AND GROUND FUNCTION CHECKED THE FLAP SYS SERVICEABLE.