Unplugged wire could be my problem(?)

I posted up recently that I was having problems with my heater settings that it would only go onto the windscreen and wouldn't switch off when i pulled the key out or turned the engine off.
Well while dismantling the dash I noticed a connected which I have inserted a photo off. the yellow ring is the clip and i've circled what it is coming off in red. Any ideas to where it goes? I've searched and I can't find where it goes to. Thoughts greatly thanked

Well while dismantling the dash I noticed a connected which I have inserted a photo off. the yellow ring is the clip and i've circled what it is coming off in red. Any ideas to where it goes? I've searched and I can't find where it goes to. Thoughts greatly thanked

