On the outdoor temp sensor where the red light does flash there are just -- - and -- - for temperature and humidity, has the sensor failed and are they repairable?
As the console still works and maybe the rain guage, not checked as it isn't somewhere where it gets rained on, I would quite like to get it working again and maybe test it out on a linux machine that I have.
The rain and temp/rh transmitters are interchangable. So you could put the rain transmitter on the temp/rh sensor to see if it's the transmitter or sensor that has failed.