Constitutional morality refers to the unwavering commitment to the principles of the constitution like equality, freedom, secularism, social justice etc.
It is not just following the constitutional provisions in words but also showing the respect for the spirit of the constitution.
Dr. Ambedkar was a great supporter of constitutional morality and he opposed religion-based morality on grounds that it supported caste system.
Constitutional morality says that we must follow the constitutional values, not just in letter but also in spirit. This also means that we must do what the Constitution would have wanted us do, in the absence of an explicit directive.