2008 Nissan Maxima service engine soon light

My husband has a 2008 Nissan Maxima an the service engine soon light is on an we tried everything an its not going off but its turns on an off? Should we unplug the battery an re do it please help

No, you should take it to a well recommended independent mechanic so they can pull the codes and diagnose what is wrong with your vehicle before repairing it