Heater blower won't work!

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DRIFTBOY
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Post Mon Jul 24, 2006 8:45 pm

Hi all!

I'd be VERY greatful for a bit of help if anyone knows much about E30 heater blower electrics.

Electrics are not my strong point!!! 8O

I have no feed to the heater switch (I think the green and brown wire ??), fuse and relay are both ok.

Is there another fuse hidden somewhere ? Or a resistor pack somewhere ?

I'm sure it worked before the car came off the road for it's 3.5 engine.

I'll go grey and bald soon if I'm not careful!!! :cry:

Thanks dudes!
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Brianmoooore
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Post Mon Jul 24, 2006 9:52 pm

No blower is usualy a seized motor.There is a resistor pack, but it takes no part in the proceedings when on full speed.
Feed to the heater switch is the green/brown, and comes from fuse 20.
Is there power on fuse 20 (ignition on)?
Fuse 20 is fed from relay K7. This can be temporarily bypassed by shorting pins 30 and 87 of its socket.
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DRIFTBOY
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Post Tue Jul 25, 2006 1:04 am

Cheers for that!

The motor does spin ok - I suppose I can check that by feeding it directly with a supply too - but I will try that with the relay pins tomorrow.

Many thanks! :thumb:
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jcjdavis1
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Post Tue Jul 25, 2006 6:24 pm

Hi I had similar prob.with my demist motor.
I got two pieces of wire and put a spade connector on each end.
Top end I put a 30amp fuse bottom ends I put in fuse no's 20 and 16
not had any bother since.
I am sure somebody will tell me that this is dodgy.
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Brianmoooore
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Post Tue Jul 25, 2006 9:29 pm

This is dodgy!
BMWs are probably equipped with the highest quality and best designed electrics found on any car.
Why not repair it properly?
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DRIFTBOY
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Post Wed Jul 26, 2006 9:01 am

Well I bridged the relay terminals as suggested and the blower worked!

No power to fuse 20,

Any ideas what could cause that?

Many thanks.
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Brianmoooore
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Post Wed Jul 26, 2006 9:09 am

Obviously, a dud relay could be the problem, but the problem is much more likely to be to do with a black/green wire that connects to the smallest terminal on the starter motor.
I've covered this several times in the past. A search should bring up all the info you need.
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DRIFTBOY
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Post Wed Jul 26, 2006 10:47 am

You are a star!

I think I know of the wire you mean so will check that out (then put the rest of the car back together).

Many thanks! :thumb:
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robmpulse
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Post Wed Jul 26, 2006 1:39 pm

PLEASE KEEP US UPDATED IF THIS FIXED YOUR PROBLEM.....MY BLOWER MOTOR WENT OUT LAST WEEK. I LIVE IN FL AND HAVE THE TOP DOWN 99% OF THE TIME I AM IN IT....SO I HAVEN'T REALLY NEEDED IT.....BUT WINTER WILL BE HERE BEFORE I KNOW IT....
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DRIFTBOY
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Post Thu Jul 27, 2006 10:49 am

I will do.

This link might help you, I have had no luck yet though!

http://www.e30zone.co.uk/modules.php?na ... ic&t=40062

I feel a hair turn grey every time I think about it! :cry:
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DRIFTBOY
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Post Sun Aug 06, 2006 9:51 pm

Hi robmpulse!
I've fixed my heater at last!

All I did was cut the green and black wire going to pin 15 of the E30 C101 connector. Then I connected the end from the loom (not the bit of wire coming from the pin in the connector) to the smallest terminal on the starter motor. This way it works through the unloader relay and switches off when the starter is cranking.
Bear in mind my problem was due to fitting an E34 535i engine so may not be the same as your problem, but I said I would let you know!
I presume you have done the usual checks - fuse, relay, the motor itself etc.?
Good luck!
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