Through-Silicon-Via (TSV)-based three-dimensional ICs (3D-ICs) have gained increasing attention due to their potential in reducing manufacturing costs and capability of integrating more functionality into a single chip. One of the most important factors that affect 3D-IC yield is the integrity of interconnects which connect different dies in a 3D-IC. This paper proposes a Design-for-Test (DIT) scheme that can 1) detect faulty interconnects in 3D-ICs, 2) pinpoint open defect locations to help yield learning, and 3) repair faulty interconnects caused by open defects to improve the 3D-IC yield. Experimental results show that the proposed scheme can achieve a diagnosis resolution of 84% for open defects. With the interconnect repair mechanism, the 3D-IC yield is improved by 10%. In addition, cost-benefit analysis reveals that the proposed technique can significantly increase the net profit, especially when the natural interconnect yield is low.