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DISCUSSION => Interior => Topic started by: anthonymax007 on April 11, 2012, 08:24:56 PM

Title: Blower Control Switch???
Post by: anthonymax007 on April 11, 2012, 08:24:56 PM: Hi everyone,

I'm not able to get the fan working for the ac/heat in my car. All the fan speeds were working a few days ago and the A/C was cool. Yesterday the fan wouldn't even turn on, and the blue A/C light wasn't coming on either. I replaced the resistor last fall, and everything was working fine until yesterday. At first I thought there might be something wrong with the blower control switch (part #61311381201) but the A/C light turning on is making me think that it could be something with the wiring behind the panels???? Anyone have any suggestions?
Title: Blower Control Switch???
Post by: DesktopDave on April 12, 2012, 05:19:29 PM: You can test the switch pretty easily, with a continuity tester. I think it's in the Bentley and the BMW ETM. From my experience it's usually the control bits rather than switchgear and/or wiring.

My A/C has never worked, but from what I understand there's the aux fan resistor itself. If that's burned out, the can won't be switched on at low speed by the A/C and the system won't start. There's also a diode in the fuse box that can prevent the aux fan from switching on.

So I'd test the aux fan with a jumper at the fanstat on the radiator.
Title: Blower Control Switch???
Post by: anthonymax007 on April 13, 2012, 02:37:28 AM: Hmmmm...I'm not familiar with where that is. Do you have a picture that I can use for reference?
Title: Blower Control Switch???
Post by: DesktopDave on April 13, 2012, 04:14:28 PM: It's mounted to the frame of the front fan. Look through the grille on the left side, there's a little tubular ceramic metal bit wired inline and mounted to the fan's frame.

http://e30.bmwdiy.info/aux-fan-resistor/index.html
Title: Blower Control Switch???
Post by: anthonymax007 on April 14, 2012, 06:56:50 AM: Gotcha. Thanks for the link, I'll take a look at it today!!
Title: Blower Control Switch???
Post by: anthonymax007 on April 23, 2012, 10:09:25 PM: Well, it's not the switch. Maybe a fuse is blown? I tested them earlier, but it's always possible I missed one. Any idea which one it could be?
Title: Blower Control Switch???
Post by: Nick_318is on April 25, 2012, 10:09:23 AM: Does the fan speed selector work at any speed with or without it on? If it only blows on 4 you need a new resistor board.

The part from pelican parts (http://www.pelicanparts.com/cgi-bin/smart/more_info.cgi?pn=64-11-6-912-633-M6&catalog_description=Blower%20Resistor%20for%20A%2FC%2C%20325e%2Fes%20%28from%2009%2F84%29%2C%20318is%20w%2F%20M42%20%281991%29%2C%20325i%2Fis%2FiC%2FiX%20%281984-91%29%2C%20M3%20%281987-91%29%20)

It's easy to change, here is a walk through from e30 tech.
How to Fix: Heater blower only works on high (4) speed [with new pictures] (http://www.e30tech.com/forum/showthread.php?t=51000)
Title: Blower Control Switch???
Post by: anthonymax007 on April 25, 2012, 01:25:45 PM: I doubt it's the resistor. I replaced it this last fall, and the fan is not working at any speed. I'm starting to suspect a blown fuse. Any idea which fuse controls the fan?
Title: Blower Control Switch???
Post by: 318kid on May 03, 2012, 09:03:09 PM: Fuse should be 20. I pulled fuzes today too, except it didn't fix my problem. My motor stopped working and then intermittently worked for a few days (lower air output) and then it stopped all together. I'm just waiting till I get te time to swap dashes to run that problem down too, but the Texas heat sure is getting to me!
Title: Blower Control Switch???
Post by: anthonymax007 on May 08, 2012, 01:00:09 PM: Thanks for the info 318kid. I replaced the #20 fuse and it seems to have fixed the problem. Hopefully that's all that needed to be done!