What was found
(CAN) DURING CLIMB, FLIGHT CREW RECEIVED A, FLAP POWER, CAUTION MESSAGE AFTER SELECTING FLAP, FROM 5. FLIGHT CREW TRIED TO MOVE THE FLAPS BACK TO 5 DEGREES WITH NO SUCCESS, FLAPS REMAINED AT 3. THE AIRCRAFT RETURNED AND LANDED WITHOUT FURTHER INCIDENT. MAINTENANCE TRAVELED TO THE ACFT LOCATION, MOVED FLAPS TO 5 DEGREES AND INSPECTED THE FLAP PRIMARY/SECONDARY DRIVES SYSTEM. THE ACFT WAS FERRIED TO A MAINTENANCE BASE WHERE ISOLATION SOLENOID VALVE ELECTRICAL CONNECTOR 2752-P3 WAS FOUND AT FAULT. THE CONNECTOR WAS REPLACED AND THE SYS TESTED SERVICEABLE.