Customer wanted me to look at a 2018 Trane unit that was operating; but may have taken damage due to a weather event and had been making a loud noise. I found that the upstairs system had a failing capacitor and a contactor (outdoor unit). These parts seemed to have taken damage due to a weather event or power surge. I replaced the capacitor and contactor on the outdoor unit and tested the system and checked refrigerant pressures. The upstairs system was operating at the end of service call.