How do I make my aux. fan come on? - PeachParts Mercedes-Benz Forum

braverichard · #1 11-01-2004, 09:28 PM

I'm kind of getting worried that my aux. fan hasn't been on for a while. Even after driving in traffic, or on the highway, when I get home and check I see that it is off. So now I'm wondering if the thing even works. What can I do to bring the temperature up high enough to a level I know should make the fan start?

tangofox007 · #2 11-01-2004, 09:38 PM

They are usually controlled by a coolant temp switch and an a/c refrigerant temp switch. Find one of the switches and jump it. Fan should come on. The a/c switch is usually on the receiver/dryer. Not to be confused with the pressure switch on the receiver/dryer.

Yes, on the receiver/dryer, look for a switch with two pigtails about 4 inches long. (The pressure switch should have two spade connectors on the switch itself. You don't want that one.) Disconnect the pigtails. Jump the two wires (the ones not connected to the switch) and the fan should operate.

Make sure that the ignition switch is "ON" when doing the check. Engine need not be running.

pawoSD · #3 11-02-2004, 12:01 AM

I think thats fairly normal.....the fan on our '83 rarely turns on, usually only if its hot out and the A/C is on, and mine turns on if I do a lot of stop and go driving or if I come off the freeway and sit in traffic I can hear it come on. It came on yesterday in a traffic jam for the first time in weeks, it was also pretty warm out, over 70. It also likes to come on in the warmer months when I go into the parking ramp at school, practically every single time, I think it just likes to make as much noise as it can to be noticed

Not that its hard to do that, it draws attention in general

#4 11-02-2004, 03:38 AM

Quote:

Originally Posted by pawoSD

I think thats fairly normal.....the fan on our '83 rarely turns on, usually only if its hot out and the A/C is on, and mine turns on if I do a lot of stop and go driving or if I come off the freeway and sit in traffic I can hear it come on. It came on yesterday in a traffic jam for the first time in weeks, it was also pretty warm out, over 70. It also likes to come on in the warmer months when I go into the parking ramp at school, practically every single time, I think it just likes to make as much noise as it can to be noticed

Not that its hard to do that, it draws attention in general

I agree on the 'draws attention'
I always try to hit about 1600rpm when driving up the school parking garage becuase it resonates with the structure and makes for an interesting show with the car alarms!
My fan? Barely ever on...only in the summer it seems..
but the cooling system is pretty up to snuff...and oregon is usually wet and cold...better thermal transfer