At 0645 hours, the structure assignment was dispatched to the 3100 block of Marion Street for a possible fire in the wall. E11 on scene prepared the reveres lay to a secondary water supply. The E11 crew made entry, helped open up the wall and crews found a burnt wire with smoke stains. The resident hit the fire with a dry chemical fire extinguisher prior to our arrivals. There was no extension and the crews were released by Asst 13.