I was called to perform a diagnostic on a Goodman heating and cooling system. I arrived at the customer's home and began by inspecting the unit's electrical connections and components. I then checked the unit's refrigerant levels and pressure and performed a leak detection test. After that, I cleaned the unit's air filters and inspected the blower motor and condenser coil. Finally, I tested the unit's operation and made any necessary adjustments to ensure it was running properly.