Fuses burning out with the interior fan switched on - Cab

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markysparky
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Post Sun Mar 25, 2012 10:58 am

Hi, Was wondering if someone could help me diagnose a recurring problem with my E30 325i Cab. Basically when you have the heater fan running the fuse burns out in no time?

Thanks
Grrrmachine
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Post Sun Mar 25, 2012 11:14 am

does "in no time" mean a few minutes, or instantaneously?

If it's instant, you've got a short somewhere. If it works for a little bit (even seconds) and then breaks, then your fan blower probably needs some maintenance:

http://www.e30zone.net/e30zonewiki/index.php/Heating
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markysparky
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Post Sun Mar 25, 2012 11:38 am

It normally works for around 5mins with the fan on position 3 or 4. It is operational until the fuse burns out. Tried a 30 amp fuse, lasted longer but still burnt out eventually. Thanks for your reply.
Grrrmachine
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Post Sun Mar 25, 2012 11:44 am

Heater blower should be a 30A fuse, in position 20. What fuse was in there before?

Get the motor out and lubricate it, based on these steps:

http://www.e30zone.net/e30zonewiki/inde ... nly_on_Max
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Brianmoooore
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Post Sun Mar 25, 2012 12:07 pm

As above. Fuse should be 30A.
Get the motor out and lubricated properly ASAP - it can't be done properly without removing it.
In the meantime, avoid having the fan switch on any position other than off or full, or you will destroy the fan speed resistor.