What was found
AFT CARGO DOOR EICAS MSG IMMEDIATELY AFTER TAKEOFF (APPROX 100' AGL)REMAINED ON AT LEAST THRU 5000' ON DESCENDING, FOR RETURN TO PDX(<P>INSPECTED AND FOUND CARGO DOOR INDICATION INTERMITTENT. TRANSFER TO MDDR 184404, CAT C DUE 04MAY23. MX ACTIONS COMPLIED WITH. PLACARDS INSTALLED. DISPATCH JT 0153Z IAW MEL 52-71-01-01. LOG PG 1749659 REMOVED AND REPLACED GROUND HANDLING RELAY PER B767 SWPM 20-81. OPS CHECKS GOOD PER AMM 52-35-00-912. NO FURTHER DEFECTS FOUND. THIS CLEARS DMI 184404 </P>)