Auxillary Fan not working. Lower Raidiator hose cold.

[enokawa]

PROBLEM #1

I recently made the wiring repair to the 3 wires that connect to the thermostat housing; however, my auxillary fan still does not turn on even when I turn on the AC.

I used a paper clip to jumper the 2 wires to the thermo; but the aux fan still won't turn on. So, it's not the relays.

Fuses are fine.

So that leads me to believe it is the resistor on the Aux Fan. What do you guys think? If so, does anyone have some advice on switching out the aux fan resistor?


PROBLEM #2

Last nite, I installed a new thermostat. After the install, the resivoir tank cap was removed, turned the heater on, started the car, and squeezed the hoses to burp the system.

Once up to temp, I noticed my lower radiator hose was cold and the top was quite hot. I put the old thermo back in and the lower rad hose is still cold so I don't think it's a stuck thermo. Bubble in the system? Or clogged radiator possibly?

[enokawa]

I always ask ask ask and have rarely contributed due to my limited knowlege.

But one thing I can contribute is the following website that shows detailed diagrams: www.realoem.com I just came across it and it definately comes in handy. That is my good deed of the day.

[enokawa]

bump

[Bry]

When your car gets warm enough, does the aux fan kick on to the high speed setting? If so then it sounds like your resistor is bad, which they do go out. If it doesn't kick into high speed, then you have a problem with getting the power to the fan.

The resistor is very easy to get at, you need to remove your front bumper, and the resistor is screwed into the aux fan housing. It is a big ballast resistor, you will see it. Just cut the old one out and solder the new one into place.

About your thermostat, are you saying that if you are driving, the car just keeps heating up? Or does it continue to get warmer as the car sits? Those are different problems there.

[enokawa]

Thanks Bry, I like that pic of your M3 at speed.

The aux fan never works. I hear a noise of some sort when I turn on the AC but the fan never turns on. I ordered a new resistor and will install it asap.

Regarding temp, my e30 heats up at stop lights or sitting at idle too long. It seems it will definately go into the red unless I turn on the heater or start driving. When I'm driving, it does run cooler yet still a tad bit hotter than I beleive it should. I have a radiator on the way. Hopefully this will remedy the situation.

[Bry]

Thanks for the compliment, I think it is a really cool pic too

If the aux fan never comes on, then you have a problem there. Are you sure that you pinned the wires properly to the temperature sensor? There are two wires, one for low speed, one for high speed, and the other is a ground. If you hook them up wierd, it won't run the fan. Also did you make sure to jumper the low speed with the ground, and the high speed with the ground? If you jump the low speed with the high speed, nothing will happen. Check the other thread that is going right now on which wire is which, that should help.

Since your low speed or the high speed isn't working, it probably isn't your ballast resistor, since you aren't getting power to the high speed either. The high speed setting should turn on at about 3/4 temperature on the gauge if your wiring to trigger the relay is set up correctly. First make sure your wiring is connected properly, then you can start to trouble shoot further down the line like if your getting power through your relay, and then if the power is getting to the fan. There are a lot of things for the power to go through.

The reason for it heating up at stoplights will be the aux fan not turning on. Don't worry about a radiator unless yours is old and leaking, that won't really solve your problem overheating at a stop.