heater blower new problem

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telboy
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Thu Jun 11, 2009 10:24 pm

my heater blower was blowing fuses so soought advice from the forum and it turned out to be the fan was seized....so i freed it with wd40 and put it back together....it started working on no4 but kept cutting out till eventually it stopped altogether...so i buy asecond hand one on ebay ...fitted it tonight still nothing ..tried the old one again after more wd40 and nothing
checked fuse and its fine
checked relay k7 but door mirrors work (thread on here)

could it be the resistor i have located it but how do remove/replace it
thanks
A1BMW325iSport
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Thu Jun 11, 2009 10:30 pm

resistor or switch?
telboy
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Thu Jun 11, 2009 10:36 pm

where would i find the switch....ta
telboy
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Thu Jun 11, 2009 11:19 pm

forgot to add there is a clicking sort of noise from the engine compartment
ucpsale
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Fri Jun 12, 2009 1:23 am

The bearings have gone on the blower motor, you need a new blower motor.
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Brianmoooore
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Fri Jun 12, 2009 9:57 am

The clicking is a self resetting thermal fuse in the resistor pack. The circuit is overloading, but not enough to blow the fuse.
telboy
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Fri Jun 12, 2009 9:08 pm

would i cure this by changing the resistor
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Brianmoooore
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Fri Jun 12, 2009 10:54 pm

Only if the thermal fuse is faulty. The chances are that it's just doing its job, and protecting the resistor pack, and that the motor is drawing excess current because of damaged/seized bearings.
telboy
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Sat Jun 13, 2009 12:28 am

but it does it on both blower motors one of which i have just bought second hand but was tested and also turns perfectly freely with no stifness or bearing noise whatsoever..............is ther anyway to test thse motors...in laymans terms as i am a complete electrical novice ie....blue wire /brown wire etc.. thanks
Last edited by telboy on Sat Jun 13, 2009 12:31 am, edited 1 time in total.
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Brianmoooore
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Sat Jun 13, 2009 12:31 am

telboy wrote:but it does it on both blower motors one of which i have just bought second hand but was tested and also turns perfectly freely with no stifness or bearing noise whatsoever
In that case, the original motor probably killed the thermal fuse.
telboy
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Sat Jun 13, 2009 12:36 am

right....bear with me please brian like i said i am an electrical novice.. is the thermal fuse on the resistor which is to the right of the glove box....if so do i need to change this or just part of it..thanks
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Brianmoooore
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Sat Jun 13, 2009 1:08 am

Assuming you have the later type heater with no aircon, then it's all in the brown clip in piece in the side of the heater box, under the glovebox.
Pull it out, and see if it all looks OK. The parts are all fairly obvious.
telboy
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Sat Jun 13, 2009 1:18 am

thanks brian i,ll check it out over the weekend
telboy
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Sun Jun 14, 2009 6:18 pm

ok took the brown clip out and this is what i found...i,m still none the wiser


[img][img]http://i124.photobucket.com/albums/p35/ ... tor010.jpg[/img][/img]


[img][img]http://i124.photobucket.com/albums/p35/ ... tor011.jpg[/img][/img]


[img][img]http://i124.photobucket.com/albums/p35/ ... tor008.jpg[/img][/img]


[img][img]http://i124.photobucket.com/albums/p35/ ... tor013.jpg[/img][/img]



[img][img]http://i124.photobucket.com/albums/p35/ ... tor007.jpg[/img][/img]
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Brianmoooore
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Tue Jun 16, 2009 12:03 am

First, there should be a steel cover over the resistors.
The thermal trip is the bit that runs across below the three resistors in your first two pics. The actual contacts are just below and to the left of the middle resistor in your second pic.
If the contacts are not actually making contact, the fan motor will not run on speeds 1, 2 or 3, or will repeatably trip and reset if the motor is drawing excess current.
The whole unit is bypassed on position 4, and the fan will operate the same on this setting, if the resistor pack is present or disconnected.
telboy
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Fri Jun 19, 2009 6:10 pm

cant be the resistor pack then as the fan does,nt run at all
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