Thank you Reinhard. I believe that the disconnected sensor wire connects to a relay which directs the power to the fan. The fan consumes a lot of power and the relay could not handle all of that juice.
What I am trying to understand is there something else in the circuit which would tell it to go on, such as a faulty high-pressure sensor on the AC or something.
Regarding the wire that looks like it has insulation coming off, it is actually the brown covering, but in this bad picture it looks like bare copper. See the second picture.
mpnye- I will wait a week and see if it dries out. That sounds like a good possibility. If so, I will dress it with silicone.
Thanks for the replies all. I will update the post when it starts behaving itself again or another solution is found.
'03 E320 Wagon-Sold
'95 E320 Wagon-Went to Ex
'93 190E 2.6-Wrecked
'91 300E-Went to Ex
'65 911 Coupe (#302580)