And this is essentially what we find in the traditional duty theories of Pufendorf, Wolff, and Baumgarten. Acting out of duty is not intrinsically wrong, but immoral consequences can occur when people misunderstand what they are duty-bound to do.
This is the example that he starts with in the Foundations, and the one that he devotes the most time to.
But does it succeed? If a maxim flunks Q2 see above but not Q1, then we have an imperfect duty to refrain from acting on that maxim.
The Fourth Antinomy contains arguments both for and against the existence of a necessary being in the world. The authority of the principles binding her will is then also not external to her will. For Kant, the feature that underlies all four of them is that we should be guided by our rational conception of duty.
This is the second reason Kant held that fundamental issues in ethics must be addressed with an a priori method: The ultimate subject matter of ethics is the nature and content of the principles that necessarily determine a rational will.
This is as explicit a contradiction as one can get. A hypothetical imperative says that if you wish to buy a new car, then you must determine what sort of cars are available for purchase. So it is the recognition and appreciation of duty itself that must drive our actions. Kant has an insightful objection to moral evaluations of this sort.