What was found
INTERMITTENT DIM FLASHING OF LT ANTI-ICE COWL VALVE OPEN LIGHT ON CLIMBOUT WITH ENGINE ANT-ICE SWITCH OFF. UPON ENCOUNTERING ICING CONDITIONS, THE SWITCH AND LIGHT OPERATED NORMALLY AND NO FURTHER FLASHING OCCURRED IN EITHER SWITCH ON OR OFF POSITION THE REST OF THE FLIGHT. WHILE WE HAD THE INITIAL PROBLEM, THERE WAS NO ANTI-ICE INDICATION ABOVE THE N1 GAUGES ON THE UPPER D/U. ACFT GROUNDED. FOUND CONNECTOR DP1303 EXTREMELY LOOSE, CLEANED, GVI, RANGE 1 COWL TAI VALVE CKS GOOD THEN RE-CONNECTED REF WDM 30-21-11. ACCOMPLISHED NR 1 ENG COWL ANTI-ICING. OPS TEST REF MM 30-21-00, OPS CK GOOD NO HISTORY.