Standard Alarm Help/ advice please.

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Chris36
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Sun Jan 25, 2009 5:44 pm

My car has the standard BMW alarm with fob. However looking under the bonnet - The alarm (with box next to siren) the wires connecting to this have been cut. I know it was cut as the siren wouldn't turn off. Car been standing for a long time..................My question is this. Would this stop the remote central locking from working. Or is the loom purely for the siren?

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DHFiS
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Sun Jan 25, 2009 6:06 pm

If ALL the wires from the alarm unit are cut its no longer able to lock the doors.
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Chris36
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Sun Jan 25, 2009 8:54 pm

AH that explains the grief then. I take it I can just splice them/solder them back together? Is there a particular pair that I need to splice? Thanks BTW
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Brianmoooore
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Sun Jan 25, 2009 9:08 pm

The alarm box under the bonnet (if it is the BMW alarm, rather than one of the BMW approved alarms) only contains the sounder and it's anti tamper battery, and a key switch to disable the alarm.
The only reason that the remote locking part of the system is disabled is because the two wires to the key switch are cut.
If you can identify these two wires (I've done this in the past, but can't remember which ones - open up the under bonnet box and trace them to the switch), then the remote locking part should work again, if still in serviceable order.
On the car I did this to, I eventually got fed up with the large box above the glovebox and the scruffy appearance of the remote fob, so it got replaced by one of the cheap 'rightclik' ebay kits.
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Chris36
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Sun Jan 25, 2009 9:17 pm

Ta - I will just solder them all tomorrow, and see where that get me. thanks for the input!!
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Brianmoooore
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Sun Jan 25, 2009 9:20 pm

If you solder them all back you will probably get a continuously sounding alarm, because of the anti tamper battery having died of old age. Probably why the wires were cut in the first place!
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Chris36
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Sun Jan 25, 2009 9:41 pm

Tits - So I need to trace the wires to the small box with the key? For which I don't have a key........
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Brianmoooore
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Sun Jan 25, 2009 9:48 pm

You don't need the key - just trace the two wires that go to the key switch, and then join the two matching wires on the car side of things together.
Make sure you have the keys, or leave a window open while you work, in case the unit decides to lock the doors.
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Chris36
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Sun Jan 25, 2009 9:56 pm

AM I being an arse or is it that easy. Don't all the wires go to that box?? The key switch.........are you meaning the small box with the on/off small key?? - sorry for my ignorance. :?
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Brianmoooore
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Sun Jan 25, 2009 11:46 pm

I don't know for certain which alarm you have.
If it's the standard BMW alarm of the period, then it will have a box under the bonnet with the sounder, a back up battery, and a keyswitch, with the alarm electronics being in a fairly large box , usually tucked up above the glove box, where there isn't quite really enough room for it. What I've written applies to this alarm only.
There were also a couple of different BMW approved alarms that were dealer fitted to E30's.
One of these was a Pirhana alarm, which had the key slot hidden from view behind a rubber boot at the back end, which also covered a couple of wiring plugs.
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Chris36
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Mon Jan 26, 2009 2:12 pm

Just an update - it is the standard BMW alaem ie. Siren, box & key. I left this completely disconnected & soldered the CL ECU, this resolved my fault - So the wires do not have to be connected to make the C/L work.
DHFiS
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Mon Jan 26, 2009 6:06 pm

No one knows more about E30 electronics than Brianmoooore, sorry for the bum info.
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Chris36
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Mon Jan 26, 2009 8:16 pm

DHFiS wrote:No one knows more about E30 electronics than Brianmoooore, sorry for the bum info.
Not at all mate. Had to start somewhere. Just glad to get the CL back. The remote doesn't work, never has!
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Brianmoooore
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Tue Jan 27, 2009 12:22 am

Your original post!
Chris36 wrote:Would this stop the REMOTE central locking from working.
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