What was found
CREW REPORTED PARKING BRAKE NOT RELEASED MESSAGE IN FLIGHT OFF AND ON, AND WOULD NOT GO AWAY. CREW DECLARED EMERGENCY INTO PIT, LANDED WITHOUT INCIDENT. MAINTENANCE DISPATCHED TO AC, TROUBLESHOT AND FOUND NR 2 EMERGENCY PARKING BRAKE PRESSURE SWITCH AT FAULT. REPLACED PER EMB AMM, OPS CHECKED PER EMB AMM. EVERYTHING GOOD, RETURNED BACK INTO SERVICE.