Heater Blowers Only Work on Max

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Kedge
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Mon Jan 16, 2012 12:03 pm

Hi,

The blowers in my touring are only working on setting 4. I've already changed the motor and tried various switches, all known working ones as tested on my 323i.

What else it there that could be at fault?

Cheers
Dave
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1bash
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Mon Jan 16, 2012 12:07 pm

CHANGE THE RESISTOR
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Kedge
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Mon Jan 16, 2012 12:28 pm

Where's that then?
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Jim320i
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Mon Jan 16, 2012 12:36 pm

In the engine bay, the centre of the bulkhead is the covering to get to the back of the matrix. The heater only working on setting 4 is down to poor lubrication on the blower... You can lube it up and hope it still works though. Mine doing the same at the minute, although after a while on setting 4, 3 starts to work, then slowly down to 1...
Kedge
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Mon Jan 16, 2012 12:43 pm

Jim, you need to learn to read, already swapped the motor for one I know is good :wink:
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Alex
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Mon Jan 16, 2012 12:48 pm

chances are its the resistor, the resistor steps down the power on 3/2/1 however on speed 4 it bypasses the resistor hence why it only works om max :D
1bash
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Mon Jan 16, 2012 12:59 pm

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Kedge
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Mon Jan 16, 2012 1:27 pm

Neither of my cars have got anything under the motor. Guessing mine is the thing on the nearside of the airbox in a metal casing, doesn't seem to pullout though. Any tips on shifting this without breaking it?
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Jim320i
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Mon Jan 16, 2012 2:40 pm

Wasnt weearing my specs. :roll:
Rtaylor2208
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Mon Jan 16, 2012 2:41 pm

Sounds like the same place as mine. Take off the under dash pannel in the glove box, then you will see a brown plastic plug going through to where the heater blower is, remove the wiring plug, then push the tabs apart. With this done go into the fan hatch in the engine bay and you should be able to give it a tap and it will come through to inside the car.

Did this last week. There is also a decent thread here with more info:

http://www.e30zone.net/modules.php?name ... r&start=25
Kedge
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Mon Jan 16, 2012 2:57 pm

Sweet, will give that a go if it's still light when i get home. :cool:
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Brianmoooore
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Mon Jan 16, 2012 3:45 pm

Assuming you don't have aircon, the resistor assembly is on the LH side of the heater box, partly hidden behind the electric heater valve.
Take off the access panel above the glove box, and it shout just be accessible, although the front centre console limits access.
It's brown in colour and is easy to find by following the several wires leading to it.
Just squeeze the tabs and pull it out - no need to dig your way in from under the bonnet as well.
The most likely thing to have gone wrong with it is that the built in thermal overload's contacts are corroded, or the plastic holding them has partly melted. This can sometimes be repaired.
The underlying cause of problems with the resistor is usually a motor in need of lubrication, so make sure the fan turns freely.
Kedge
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Mon Jan 16, 2012 9:31 pm

Cheers Brian. The motor does seem to turn fairly freely, well seems just the same as the one I took off my 323i which was working fine. I'll give them both a good lube while they're out and test them both again in the 323i before I free it of the resistor for the touring.
Oh and yes, it's non a/c, had spotted the resistor pack, just couldn't sus out how to remove as I'd assumed it would come out the top :o:
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adit
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Mon Jan 16, 2012 9:54 pm

i have resistors here Dave. just shout if you need one mate :wink:
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Rtaylor2208
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Mon Jan 16, 2012 10:29 pm

Adit I need one, how much?
Kedge
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Thu Jan 19, 2012 2:54 pm

JD :D

I'll do a quick write up for the Wiki on this I think. Does anyone know when the resistor changed to the one under the motor? I have an '86 316, '86 323i & an '88 325i touring, all of which have the resistor in the side of the airbox.
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Rtaylor2208
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Thu Jan 19, 2012 3:26 pm

Kedge did you end up having to replace the resistor? I got one from Adi but that didn't work (no complaints though as he's sorting out another) even though the motor runs freely after a bloody good clean and oil up.
Kedge
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Thu Jan 19, 2012 3:41 pm

Yea, worked perfect with both my motors. The resistor was a known warming as it came straight out another car.
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Rtaylor2208
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Thu Jan 19, 2012 4:25 pm

Cheers fella, hopefully with another one that will be another job off my list, its slowly getting shorter.
Kedge
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Mon Jan 30, 2012 5:37 pm

Now added to the Wiki ready for plenty of contructive criticism :)

http://www.e30zone.net/e30zonewiki/inde ... nly_on_Max
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