my cooling fan never comes on on my 2004 x350, even when the a/c is on. I have checked the 10 amp & 80 amp fuses, both are good.. That would leave the fan motor, coolent temp sensor, or the plug connection on the fan harness... Am I missing anything?? The car has 161000 miles on it. Coolent sensor is plugged in.. How can I tell if the sensor is bad or the fan motor is burned out?? Any help is much appreciated 😃

 

I think my fan has been on once or twice since I got the car. My old '97 that I had for for 16 years went on more when it is hot. But I don't recall it turning on. When I had the top radiator hose pop off last October (driving it for 10+ minutes before I noticed that it wasn't sounding right and without the temp gauge budging from the mid point), I now have a wireless (bluetooth) ODB sender and "Torque" on my android and I constantly check the real temp just to make sure there isn't another problem (with my radiator leak that I just fixed, I was watching it all the time to make sure there wasn't a problem). When I would expect it to go on is on a really hot day (next Sunday it is supposed to be pretty hot in the bay area (I'm in Campbell), so if I drove a bunch with the AC on and stop and go, I would expect it to go on. I don't know off hand what the temp is set to for the fan to go on, but I know it doesn't automatically go on when you turn the AC on; it only goes on when the temp gets to a certain point. I seem to remember it being something like 220-225f, but I haven't seen my temp go over 210 in a while. If you don't hear anything else from anyone, I'll let you know when it is hot with the AC on and stop and go and let you know if/when the fan goes on, and if so, what the temp is. Do not rely on the temp gauge in the dash; based on what I heard about the logic, I suspect by the time it starts to move up, you are already in dangerous territory.

 

I replaced the radiator about a year ago, re filled the system, and drove it locally for almost a year here in the East Bay Area. One day, after driving on the highway a bit, I parked in a parking garage and noticed some coolent on the ground when I left... It also left a puddle in my parking space... The system may have been slightly overfilled at the time, I have driven it since with no puddles, so I was concerned. I will recheck to see if the fan blades spin freely this week, but I really hate it when the car "fixes itself" After the puddles, the next morning, the coolent level was just about at the lower step in the header tank... Problems or not?????