FRENCHTOWN TWP. (WWJ/AP) – DTE Energy Co. says the reactor at the Fermi 2 nuclear power plant has been shut down after a problem with a system used to cool auxiliary equipment. Utility spokesman Guy Cerullo said the manual shutdown took place late Sunday after workers discovered an issue with the plant’s cooling system. “Essentially it stopped working,” Cerullo told the Monroe News. Crews will evaluate plant equipment and look to see whether any repairs are necessary. Power customers shouldn’t notice any changes with the shutdown. Cerullo said the plant had been operational for 163 days without a shutdown. A possible restart date wasn’t released by Detroit-based DTE. The plant is located along Lake Erie in Monroe County’s Frenchtown Township. TM and © Copyright 2015 CBS Radio Inc. and its relevant subsidiaries. CBS RADIO and EYE Logo TM and Copyright 2015 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.