Post Reply
jrreeve
Gold
Gold
Posts: 83
Joined: Wed Dec 01, 2004 5:40 am

Fan resistor

Post by jrreeve »

Hey all, i've just been messing with the car lately (getting read to sell it!) :( . I noticed the resistor for the heater fan on the firewall today. That only controls speeds 1 and 2, correct? What controls the high speed on the heater fan? My memory is hazy on this one, isn't it wired direct, anyone remember what color the wire is? I don't seem to have the high speed on it, which isn't making sense to me. The wiring diagram is a bit of a nightmare.

Thanks,
Rob
'84 GTV
'91 164S
User avatar
x-rad
Verde
Verde
Posts: 1223
Joined: Sat Mar 05, 2005 1:21 pm
Location: Canton, Ohio, USA

Post by x-rad »

kinda of complex but:

red from fuse 7 to common on fan switch
then distributed to low, med, or high

if on high setting, then yellow out of switch directly to fan

if medium, then yell w/black out of switch to middle section of resistor, then yell w/black back to common junction at high section of switch, then to fan (on common line which becomes yellow on the way to fan)

if on low, then purple out of switch, changes to pink at connector, then to resistor end, back out resistor using yellow w/black back to fan switch to the high setting line (common line which becomes yellow on the way to fan)

the power out from resistor is a shared line which joins the high line to fan at switch. basically shares power directly from three sources, two from common yell/black from resistor and one directly from 12 source through switch.

since all power comes from fuse 7, it is probably a switch problem if you don't have high speed

this from wiring dgm 1984...
Frost
Silver
Silver
Posts: 37
Joined: Wed Jul 09, 2008 6:15 am

Re: Fan resistor

Post by Frost »

Please HELP,I have a 75 twinnie and no owner manual or any published material for the car and the fan doesnt work at all e.g no fan speed works,its a non AC car and Ive checked all fuses,they are fine :?
User avatar
Maurizio
Verde
Verde
Posts: 680
Joined: Wed Dec 01, 2004 4:49 am
Location: the Netherlands, 153.1km from the N'ring :-)

Re: Fan resistor

Post by Maurizio »

Frost wrote:Please HELP,I have a 75 twinnie and no owner manual or any published material for the car and the fan doesnt work at all e.g no fan speed works,its a non AC car and Ive checked all fuses,they are fine :?
http://www.users.on.net/~craigf/
Banned.. ? ;-) Daily donky.. ==> BMW 325d Image
E36M3 (3.0) Ringtool :twisted: ==> definitely BANNED!

AR 75 TS Ringtool '90, AR Spider 2000 veloce '79
floridamary4
Silver
Silver
Posts: 3
Joined: Sat Jun 26, 2010 7:12 am

Re: Fan resistor

Post by floridamary4 »

thanks for postings :)

Heating Repairs
Post Reply