It's a Intake manifold air pressure sensor, I snapped mine at the other end but found a seller on ebay flogging them cheaper than anywhere else.. You can't just get the tubed part (I checked) search for item 261338465825 & you'll find it looks the same as your part. I taped mine up initially & it seemed to run OK, blanking the EGR made a big difference on mine. I did replace the tube & sensor in the end in part because it was so cheap & easy just to unbolt the sensor, pull the tube off & refit.
It's the ice warning light (it looks a bit like a snow flake), when we 1st got our Focus the wife frightened the life out of me (in a snowy December) by ringing me at work to say the new car hard a red cog on the dashboard!!! If I remember correctly I think if the temp is something like 1-4'C it shows amber & 0'C or below shows red. If in doubt check the owners book as it will show you the symbol you are seeing.