radiator fan & other stuff! - United Bimmer Community

**jonspencer_1981** · 05-03-2007, 05:04 AM

I've recently accquired my 3 series, and had the rad replaced straight away. It was cracked and overheating.
The mechanic says i have to keep my air-con on as when the motor kicks in, my fan works. When the air-con if off, the fan won't work to cool the rad down.
Is this normal? Is there a way to link a direct switch from fan to ignition on/off?
The air-con motor seems to be making a funny noise which i have put down to a bearing. Can the bearings be replaced, or would it have to be the whole unit?

Thanks in advance...

drz · 05-03-2007, 03:51 PM

It sounds to me like your temperature-activated auxiliary fan switch is not working. The reason your mechanic tells you to keep the AC on is because whenever the AC is on, the auxiliary fan kicks on. However, it should also come on whenever your engine reaches a certain threshold.

Check out this link: http://www.realoem.com/bmw/showparts...89&hg=17&fg=05

The part I mention has part number 61318376440 and is item #10 in the figure to which I linked above.

Always check with your mechanic or somebody mechanically knowledgeable before working on your car.

Best of luck

drz · 05-07-2007, 12:35 PM

Quote:

Originally Posted by jonspencer_1981

I've recently accquired my 3 series, and had the rad replaced straight away. It was cracked and overheating.
The mechanic says i have to keep my air-con on as when the motor kicks in, my fan works. When the air-con if off, the fan won't work to cool the rad down.
Is this normal? Is there a way to link a direct switch from fan to ignition on/off?
The air-con motor seems to be making a funny noise which i have put down to a bearing. Can the bearings be replaced, or would it have to be the whole unit?

Thanks in advance...

A "thank you" would have been nice. I went and did this research for you, then you come back to the board and don't even bother to say "Thanks, I'll let you know if this works." Anyhow, have you had a chance to check w/ your mechanic?

**jonspencer_1981** · 05-07-2007, 01:19 PM

sorry chap, not quite used to the forum yet.
Not been back in touch with the mechanic. I looked at the side of my radiator, and it looks like theres a blanking plug where the fan switch should be. If i were to get one, would it just be a matter of fixing it in? Does it need wiring anywhere?
thanks in advance

drz · 05-07-2007, 02:14 PM

Good to hear from you again. Well, a harness with three wires does plug into the back of the fan switch, so you may have some stary wires somewhere in your engine bay. I will not be able to check this out in my car in the next couple of days, but if nobody else has chimed in by then, I'll try to track those wires and see where they go.

**c1apton** · 05-07-2007, 08:57 PM

You can manually overide the switch by hooking a toggle switch to the relay. I'm not familiar with your eng. bay but on the E34s there is a small relay box on left front inner wheel well with 3 relays for aux fan.

**jonspencer_1981** · 05-08-2007, 04:12 AM

The mech said it may be possible to put a switch relay in, which i did consider.
drz - there is a group of three wires, which i will add "wasn't" connected when I bought the car. I noticed and thought it wasn't right, so connected it. I tried to follow where they lead, so I could put a swaitch in, but got lost half way! (black wires, black engine bay, easily done!)
c1apton - the switch idea sounds good, but if it wasn't initially needed, surely there should be no need for it now?

I'll try and get pics of the radiator to show if the aux fan switch is there or not? You never know, you may be able to see it clearer than me!

**c1apton** · 05-08-2007, 05:19 AM

Go to www.Realoem.com and enter the pertinents of your car and check out the diagrams.

**jonspencer_1981** · 05-08-2007, 05:41 PM

cheers c1apton, drz researched the diagram for my exact radiator, and it seems I have a part missing. I'm not sure if I've got a blanking plug, or if my radiator shouldn't have a sensor.