Will someone explain how aux fan works, on my 93 Mercedes 190e in the morning when I turn the a\c on the aux is not on, it comes on about 20 minutes latter.. at first I thought it was because it was low on freon .so I top it off.this morning. still 20 min after start up then it finally came on. . I check my w 140 and its the same way .but I'm still a little confused about the aux fan to how it really works as far as the drier switch high and low relays. will someone please explain to me how it works I really do appreciate everything you guys do thanks you very much.