On 05/23/2015 at 1230, Company 20 was alerted to assist Company 14 for a structure fire. Engine 201 and Unit 202 responded with a total crew of 4. Further information from MECCA advised that residents heard a loud pop and then noticed smoke coming from the wall. Engine 141 arrived on scene with light smoke showing and staged Engine 201 and Unit 202. A small fire was found inside the wall and was extinguished.