Charleston County Aviation Authority spokeswoman Becky Beaman said the plane landed in Charleston about 11:30 p.m. Monday as a precaution.
Beaman said a mechanic with a part for the 737 jet was being flown to Charleston today.
She said the mechanic was expected to repair the plane and the 160 passengers would continue their trip to Washington. They spent the night in hotels.
There were no injuries.
Officials with American Airlines did not immediately return a phone call seeking comment.
Beaman said the flight, American Airlines 1012, had originated in New Orleans.