Blower Fan / Switch

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Billy1972
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Wed Apr 10, 2019 12:06 pm

Hi, my fan switch only works on setting 4 now in my 1987 325i vert?

Is the culprit a faulty 'Heater Blower Fan Resistor' from what I've looked up or could it be something else?

If it is the Fan Resistor is it a difficult part to get at and replace?

Thanks
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BenHar
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Wed Apr 10, 2019 1:09 pm

Billy1972
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Wed Apr 10, 2019 4:38 pm

Outstanding thanks Ben, i'll be ordering a Resistor for starters tomorrow!
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GPW
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Wed May 15, 2019 6:47 pm

Handy thread as mine died today in my convertible, where is the best place to get a new one of these brown resistor packs?
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BenHar
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Wed May 15, 2019 9:00 pm

Probably BMW.

Ben
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GPW
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Wed May 15, 2019 11:24 pm

Ok so an update, there's a contact in this resistor pack like in a relay, and while I was cleaning the contacts with a bit of paper (just as I thought it may be a dodgy contact) I went around to the other side and noticed a hairline crack.

I suppose it's a bimetallic strip to shut-down if it gets too hot. The crack also shuts it off...

This explains why the failure was quite sudden, one moment for 33 years it wa fine, then today it wasn't. So anyway I scraped it a bit with a screwdriver and it seemed to clean up nicely and looked eminently solderable, so I popped a blob of solder over it and it now all works perfectly again.

So there you are, if yours fails in the same way, clean up around the crack and solder it: job done, money saved.

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Someone could put this in the wiki/etc if they like, you can use my pics here without any issue.
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