What was found
AFTER DEPARTING FROM DCA, THE CREW RECEIVED A WEIGHT ON WHEELS CAS MESSAGE AND ASSOCIATED PROXI SYSTEM FAIL CAS MESSAGES. FLIGHT 4031 WAS INSTRUCTED TO DIVERT TO PIT THEN DECIDED TO CONTINUE TO DAY DUE TO RUNWAY CONDITIONS AT PIT. AFTER VERIFYING THE GEAR WAS DOWN AND LOCKED, FLIGHT 4031 LANDED SAFELY AT DAY. MAINTENANCE INSPECTED AND REPLACED THE LEFT HAND DATA ACQUISITION UNIT IN ACCORDANCE WITH DORNIER MAINTENANCE MANUAL 31-00-00. OPERATIONAL CHECKS WERE PERFORMED AND THE AIRCRAFT WAS RELEASED FOR SERVICE.