An approach for testing, including a self-test method, a semiconductor chip is disclosed. The approach generates test patterns, including weighted random test patterns, for testing random pattern resistant faults, and un-modeled faults directed at specific logic groups, where the dynamically generated test pattern weights are configured to optimize test coverage and test time. The dynamically generated test patterns are based on factors related to random pattern resistant logic structures interconnected via scan chains. More particularly, the dynamically generated test patterns are designed to enable fault detection within logic structures that are resistant to fault detection when tested with random patterns.