Electrical problem (alarm/immobiliser), Car won't start.

decampos

decampos

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Had a problem last week where the car wouldn't start and the alarm would sound. (I didn't install the alarm and don't know much about it). I'd reset the alarm, try and start the car - it wouldn't start, alarm would sound. I pulled out two large plugs in the back of the alarm ECU (pictured), the car then started fine. I concluded that the alarm was faulty.

Recently I've been trying to correct a few modifications to the electrical system (mostly removing remnants of a modern sound system), I decided to remove the alarm. Starting with the alarm ECU, I clipped the two wires that fed into it. Car now won't start. The whole wiring loom is a real mess (pictured) and I don't know where to begin in resolving the situation.

Any general advice in removing the bits that aren't meant to be there and fixing the problem of the car not starting?

Any advice much appreciated.
 

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I would ask a shop that installs that type of alarm. Perhaps the two clipped wires need to connect to each other now that alarm is removed?
 
What year is your car?

Alarms usually bypass the starter and ignition key so look for those original wires to resplice them. A meter or test light would be helpful. There should only be three or so wires to chase down.

I would venture to say the fused splices just loop ( one wire splits to two- one in and one out of the ecu), but the far left orange plug looks to be the original ignition wires on that left side of the same.

Open up the wrap a bit more, show every connection ( especially the wiring colors)

Toad is in business still. They offer wiring diagrams, but you'll have to decide which system you have as they have two similar to yours.
 
Thanks for the replies. Sure enough, it's been pretty simple to remove the alarm. Is a lot of wires and general bits. According to an invoice the whole set up was professionally installed in the mid 90s but is a really amateur looking mess. Wires are spliced badly and held in situ with tons of electrical tape and millions of cable ties. Just goes to show that it's better to take the time to learn how to do these things one's self.

Anyroad, The broken black wire was for the starter motor.

I'm a bit stumped by one connection: A wire coming out of the alarm's ECU connects to something that looks like speaker wire (two wires). One wire goes to a strange original looking white connector, the other disappears under the carpet /trim. (I've just glued down a new carpet set and really don't want to tear them up unless I have no choice).

According to a helpful diagram found using a google search ( http://i227.photobucket.com/albums/dd90/thomasatladock/IMG_0771-1.jpg
), this wire coming from the ECU (a grey and white wire) goes to something called a 'boot pin switch'. Any ideas what that could be on an E9?

Any help very much appreciated.
 

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If it is an alarm then opening the trunk would set it off, triggered by the trunk light. If just an ignition demobilzer then disregard.
 
decampos said:
Thanks for your reply. I don't understand. Why would the wire connect to the light in the trunk? ...
Click to expand...


To protect the red handled screwdrivers in the toolbox of course :)

I just moved mine to my bank's safe box.
 
HB Chris said:
If it is an alarm then opening the trunk would set it off, triggered by the trunk light. If just an ignition demobilzer then disregard.
Click to expand...

Ah, right. Yeah, I get it. that makes sense. I've removed all traces of the alarm. The person that 'professionally' installed it really needs to be beaten up.


Arde said:
To protect the red handled screwdrivers in the toolbox of course :)

I just moved mine to my bank's safe box.
Click to expand...

Are they sought after?
 

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