What was found
INSPECTION TYPE:N/A, AIRCRAFT DEPRESS AT 2000'' AGL. MAIN CARGO DOOR WARNING ON EICAS. ON CARGO DOOR CONTROL PANEL, RED DOOR OPEN LIGHT ILLUM AT THAT TIME NOTICED A CARS BLOCKED US IN AND A POST LIGHT WAS FLASHING. AFTER LANDING, ALL OPS NORMAL. EICAS MSG WAS MAIN CARGO DOOR SYS. *S/D* PRESSURIZED A/C TO 8.0 PS, CHECKED OK R7 RD MAIN CARGO DOOR SHUTOFF VALVE AND PRESSURE SWITCH PER 757 M/M 52-32-09.