Installed EEV control board and sensors. I managed to get the system to start working again with the new parts, but I was met with another issue on the outdoor unit. From the attic, I heard it kick on and rushed outside to investigate. I found the contactor chattering due to bad connections at the defrost board. We need to replace the defrost board and wiring harness to ensure good connections are present. Also, I observed that the contractor is completely charred. My recommendation is a new outdoor system due to other components being in rough shape, mice have been present, and the system being 12 years old without warranty. At the minimum, we need to replace the defrost board and wiring harness. Replacing of EEV board and 2 sensors on the Trane system