When the Equinox Doctor's ethical subroutines are deleted, he is capable of doing all sorts of things he normally would not do, like killing alien life forms to turn them into fuel. I do not understand, however, why his loyalty to his captain and crew remains so strong regardless of whether he is on Equinox or Voyager. This is demonstrated in his rescue of Captain Ransom and crew members from Voyager's brig, and his repeated subterfuge communications with Equinox to alert them to Voyager's whereabouts and shield frequencies.
In contrast, when Voyager's Doctor has his ethical subroutines deleted, he does not seem to be analyzing or practicing ways to circumvent Captain Ransom's orders to save his crew member, Seven of Nine, neither through delay nor deception. He appears to simply follow all of Captain Ransom's orders.
I can understand the EMH wanting to preserve itself first and foremost when its ethical subroutines are deleted, but why would it then jeopardize its safety on Voyager by aiding the Equinox? What determines the EMH's loyalty?