I arrived to clients home for concerns that the home was not reaching desired temperature set point. I found that the upstairs unit was cooling and the downstairs unit was on but not cooling. I immediately proceeded outside and the outdoor condenser was not on. I checked voltage and it was not receiving power. I went back inside and confirmed the control board was sending the correct power to the outdoor equipment. It was. There were no burnt or compromised components to indicate a failed component. But the system had a short in power. I went back outside and was able to use an existing spare thermostat wire and rematches it to the indoor control board also. With this spare wire the unit was able to receive the correct voltage and immediately turned on. I checked the cooling temperatures and the unit is cooling with a perfect 20° drop. The unit will run for a few hours but will reach the desired set point, now that the repairs have been made.