Auxiliary Fan

[redbmw]

hey,
has anyone ever had problems with there auxiliary fan. If so, what did you do to fix it.

My fan been messed up for a long time. I've done a couple thing to try to fix it. I did the electrical test were you jump the battery straight to the fan and test for low ideal and high ideal speed. the fan cames on at high ideal speed but not low ideal speed. so i spent 30 buck and got a now switch and that didn't fix the problem. so I i pull an auxiliary fan from a wrecking yard and tested it on my car and it did the same damp thing. so i'm kinda stuck on what to check next.

[tonytony]

OT: you should come to the e30 meet/tech day on the 31st here in portland.

I have the same problem and someone told me to change the resistor on the fan

[redbmw]

did you change your resistor and did that fix the problem?

[tonytony]

i haven't gotten around to it yet, i should though since i dont have the fan clutch anymore

[winstontj]

There should also be a temp switch somewhere... in the head or the radiator that tells the fan to turn on. Pull it out, clean it up and stick it in a pot of hot water with a thermometer. Read the number on the side of the temp switch and bring the water up to that temp. Use an Ohm meter to check that the switch is working properly. If that works than I'd look at that resistor thingy... (Which I have no idea about)

[Jean]

If the fan is working connected directly to the battery, try shorting the temp switch connectors (mine is on the radiator) and see if the fan comes on. The next step would be to check the resistor mounted on the fan shroud.

[smooth]

Don't forget to check the relay...
You use an ohmmeter to test the relay, too. It's in the Bentley.
Didn't you get another resistor with the aux fan you pulled from the yard?