Return to replace 2nd floor A2L sensor, wire harness and control board. Disconnect existing wire harness, unplug molar connection. Remove old wire and install new wire harness. Disconnect wiring from control board. Installed new control board. Re-connected wiring. Ran and tested system operation. New control board is operating normally. New board is not given error code of 3 flash. New board is flashing Once for normal operation. New board is also sending call to condenser to make condenser run. System is on/running. Check and tested for normal operation after replacement of parts. A2L sensor and control board w/ wiring harness. View visual findings from this job here - https://visionshare.xoi.io/?id=XA-A3D0-89AD668D5D0943ECA3B5DAFB9FCCF502