Methods and systems provide for early and simplified testing for defects in the interconnects of a programmable logic device (PLD) and in associated software tools. Data that describes the interconnects are read from a database for the PLD. For each interconnect, a respective test design is automatically generated with the test design replacing a portion of a coupling between an input pad and an output pad in an archetypal test design with a coupling that includes the interconnect. A respective configuration is automatically generated for the PLD from each test design. A respective operation of the PLD programmed with each configuration is simulated, and each operation of the PLD for is checked inconsistency with an expected result. In response to any inconsistency, an indication of the inconsistency is displayed to a user.