PPL Corp's 1140MW Unit 2 of its Susquehanna nuclear power plant in Pennsylvania, US, has resumed operations.
A single-point wiring deficiency in the unit's digital control system led to an automatic shut down during scheduled equipment testing on 19 August.
PPL conducted inspections to detect damage before connecting the unit to the power grid earlier this week.
Susquehanna Unit 1 continues to operate at full power, the company said.
The Susquehanna plant is owned jointly by PPL Susquehanna and Allegheny Electric Cooperative and is operated by PPL Susquehanna.