Elec window reset switch

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IB6376CY
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Post Thu Feb 14, 2013 4:34 pm

Before I get into this problem perhaps somebody has solved this. The elec window reset switch no longer stays reset, but holding down, windows function. Is this a "normally open switch " as there is 12v going to it? All constructive input appreciated.
bigwinn
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Post Thu Feb 14, 2013 4:51 pm

Should operate on or off, not as a press in and hold?

Sounds like the mechanism inside the switch has failed, you can strip it down but may be easier to just grab a new one?
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Post Thu Feb 14, 2013 6:04 pm

bigwinn wrote:Should operate on or off, not as a press in and hold?

Sounds like the mechanism inside the switch has failed, you can strip it down but may be easier to just grab a new one?
Decent ones are fetching £20-£30 on ebay.
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Brianmoooore
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Post Thu Feb 14, 2013 7:21 pm

Topblag wrote:
bigwinn wrote:Should operate on or off, not as a press in and hold?

Sounds like the mechanism inside the switch has failed, you can strip it down but may be easier to just grab a new one?
Decent ones are fetching £20-£30 on ebay.
About £7.50 brand new from BMW, if the on line ETK price is anything like correct.
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IB6376CY
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Post Fri May 17, 2013 8:48 pm

Easier still, disconnect the wires at the back of the switch, insert a 30 amp fuse (as supplied in the fuse box lid) to the wire terminals, and off you go!
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Brianmoooore
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Post Fri May 17, 2013 8:57 pm

IB6376CY wrote:Easier still, disconnect the wires at the back of the switch, insert a 30 amp fuse (as supplied in the fuse box lid) to the wire terminals, and off you go!
A 30A fuse is NOT the equivalent of the cut out switch. The above advice is dangerous
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IB6376CY
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Post Sun May 19, 2013 9:19 pm

Sorry, I thought it was effectvely the same thing. However I stand corrected and would be glad if you could explain to me the difference, i'm no lecky.
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Brianmoooore
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Post Sun May 19, 2013 10:39 pm

The stall current (motor jammed) of a window motor is nothing like enough to blow a 30A fuse. The fuse is there to respond to short circuits in the wiring, where the current will be high enough to blow the fuse in a short time.
The cut out operates at a much lower current, but with a time delay. I don't know the exact characteristics of the E30 cut out, but at a guess it'll be around 8A or so, but this current will need to be sustained for some time for it to trip.
I've had direct experience of this with an E30 that had originally been manual and had been converted to electric. Whoever had converted it hadn't bothered with the cut out, and had connected the circuit to a 30A fused permanently live source - the cigarette lighter fuse.
I had been working inside the cabin of this car, and had left work in the evening, accidentally leaving a heavy object across the centre console, which was pushing down the 'up' button of the passenger window.
When I returned in the morning there was a strong acrid smell throughout the whole workshop, the passenger window motor was burn't out, the battery totally flat, and all the window wiring completely burnt out - and the fusw still intact.
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IB6376CY
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Post Thu Dec 26, 2013 4:56 pm

A belated thank you for a comprehensive explanation.
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Post Thu Dec 26, 2013 5:53 pm

it will also lessen the damage to little fingers..........
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