leightonf 7 Report post Posted July 28, 2014 Hi all, I'm trying to get the blower going in my FL 318i with A/C, which was going fine then all of a sudden stopped one day. Done plenty of research and have pulled and tested everything: switch, resistor pack and blower motor. They all seem in good working order, but the fan is still a no-go when trying to control it from the switch. There is no power at the fuse, which makes me wonder if there is a wiring issue between the battery and the fuse box (the power mirrors don't have power either). Does this sound plausible? My other question is, how do the high/low speed unloader relays work? From what I can figure they only kill the power when cranking, so shouldn't be an issue unless they are stuck open, constantly routing power away from the fuse, correct? Thanks in advance for any help, Leighton Quote Share this post Link to post Share on other sites
nick496 268 Report post Posted July 28, 2014 Yeah, would try testing/replacing the fuses/relays first. This guy reckons the K7 relay: http://bmwe30network.net/forums/read.php?3,8221 Which since your mirrors don't work, sounds like like your best bet. Swap them around for one that works. Quote Share this post Link to post Share on other sites
leightonf 7 Report post Posted July 29, 2014 (edited) Thanks for the reply, I have power at the fuse now, and the mirrors are working. But still no blower Following the sequence from that (amazingly helpful) article, it goes K7-Fuse 20-Switch-Resistor-Motor. So since I have no 4th speed and I know the blower works it must be wiring between the fuse and the resistor pack somewhere, or the switch itself. I guess I'll try jumping the switch at the connector in the HVAC panel, then if that doesn't work maybe replacing the resistor pack and/or blower just as a matter of course. Edit: Scratch the question below, the fan should work even if the switches/lights don't [is anyone good enough at wiring diagrams to tell me the significance of no A/C or recirc light in relation to how far the power is geeting?] Will report back to add to the saga that is E30 heaters.. Edited July 29, 2014 by leightonf Quote Share this post Link to post Share on other sites
UBH8N 0 Report post Posted July 29, 2014 Not sure if the setup of 318i and 320i are the same, but i had a similar problem on my 320. Turned out to be a little wire coming off the starter motor solenoid (unloader control wire i think?) all i had to do was clean it up a bit and put it back on properly. Its the top connection from memory Im not sure if 318i is the same tho Quote Share this post Link to post Share on other sites