Maintenance replaced aux pump. Air test no change. Operated door open and locked, ramp open and locked, ramp closed and locked, door closed and locked in that order using manual control. Test successful, isolated to electrical issue. This model has ADS arms ( anchor arms ) installed for aerial delivery, wiring diagram shows if these arms are loose when retracted or switch is minimally contacting the power is lost to the ramp solenoid.. Sure enough techs went out and rattled the arm finding circuit being opened and ramp solenoid de-energized. Switch adjustment in progress. Test flight this afternoon. Fix sounds promising since air loads when opening door with the ramp closed are different than with an open ramp, possibly affecting a minimal contacting arm switch. Update to follow and thanks smoedog for the suggestion.