Auxiliary Fan & AC

[Brandon12V]

This is true, but it doesn't mean they have it in stock at your local parts store on Memorial Day.

Just order online since you're doing the fuse thing. bnwmercedes.com is super cheap as well as blunttech.

[IS300E30]

My 87 325is is doing the same thing, aux won't kick on til almost in the red zone, like you it happens in slow/standstill traffic.. My tech said the fan should come on when a/c is turned on but offered no resolution to me at the time... Anyone got any ideas for this prob..... Thanks, tomwas

I can not answer nor resolve your issue. I just wanted to say you have a damn nice looking car..... :)

[leegf]

i just did this the other day. enjoy!

http://e30.bmwdiy.info/aux-fan-resistor/index.html

[tomwas]

I can not answer nor resolve your issue. I just wanted to say you have a damn nice looking car..... :)

Thanks very much, I feel I am very fortunate to have found/purchased it this past December, have had some important work done or have done some myself and it's relly a great running car, have had 15 nissan/datsun Z cars from 79 to 89 in the past and this E30 has a nice snap of accecleration and really nice ride and handling, very impressive little car.......

[andrewlobel]

I have a few questions regarding the factory Auxiliary (electric) Fan and the Air Conditioning on E30's. I have seached a few times but have not found any definitive answers.

My car is a 1990 325i and the fan clutch and water pump are less than a year old. I have noticed that my auxiliary fan does not run when I turn the AC on in my car. (this is also the time when the temp gauge will start to rise a little). Actually the electric fan will not turn on until the gauge is at the 3/4 mark on the gauge (this only happens at standstill with the AC on). Other than this my temp gauge stays around the 1/4 mark.

My Questions are:

1. Should the Aux Fan run whenever the AC is running?

2. Are there connections that I should check?

3. To me it seems that if my fan doesn't kick on till the 3/4 mark then the lower temp portion of the fan switch isn't functioning properly. Could this be a resistor problem? How do I check?

Thanks in advance for any help/advice.

Check your relays. You have two: one for low-speed, and one for high-speed, and they are located in the black box under the hood, near the firewall, on the drivers side. Normally, the auxiliary fan does not turn on unless A) you have your AC Unit turned on (and your A/C system is working properly), or B) it's a very hot day outside. The A/C and warmer temps will kick on the low-speed setting. I can't imagine anything short of racing or a desert triggering the high-speed setting. I've driven my car in 103 degree heat and the high-speed setting never kicked in, and know my relays work because I tested them. Your aux fan shouldn't be engaging at all during start-up unless you have your A/C turned on, and even then, it should be the low-speed setting at that point.