560sel Aux Fan - A/C Problem
Just getting around to fixing a high heat problem on my 560sel. When the a/c is turned on the aux fan is supposed to come on high according to Mercedes dealership. Some one, before I got my car had disconnected the green sensor on the a/c drier and took the two wires that went to the drier sensor and hooked them up to the two heavy wires that go to the aux fan. This caused the fan to run on high speed all the time. I disconnected the two wires that were mickey moused to the aux fan wires and wired them back to the drier high pressure sensor the way it should be. The fan does not come when the air conditioner is turned on. Since my a/c was a little low - I was told that a low charge would not trigger the sensor on the drier. Well, I now have had the a/c topped up so it blows nice and cold - but the high speed aux fan still won't come on when the a/c is on. I checked with Mercedes dealership and they suggested that I disconnect the two wires from the sensor and short them together and the fan should come on high. It doesn't. Is there a relay or something else I can check to try and find it? The fuses are all good - no corrosion on the tips. I have a funeral to go to in Michigan next week and I would like to fix it before I leave.
Thanks ahead of time for any help.