Help-1990 Alarm won't stop sounding
Thread Starter
Burning Brakes
Joined: Oct 2005
Posts: 999
Likes: 7
Help-1990 Alarm won't stop sounding
For no apparent reason the alarm horn started sounding on my 1990 C2. It is loud. The only way I can stop it is to disconnect the battery. As soon as I reconnect the battery it starts sounding again. The car starts and drives but the alarm continues to sound.
Any suggestions are very much appreciated.
Any suggestions are very much appreciated.
Racer
Joined: Jun 2011
Posts: 491
Likes: 20
From: Danbury, CT
I feel for you. My '90 C2 had a funky alarm like yours. I replaced all door, hood, lid and glovebox switches. Haven't had a problem since. Could be a short somewhere. Or, it could be worse and your alarm unit is shot. Best of luck and let us know what you find.
Thread Starter
Burning Brakes
Joined: Oct 2005
Posts: 999
Likes: 7
Thanks guys.
I wonder if this is applicable?: http://www.pcarworkshop.com/images/8...0192geolab.pdf
(Thanks Geolab!) It was raining here today.
I wonder if this is applicable?: http://www.pcarworkshop.com/images/8...0192geolab.pdf
(Thanks Geolab!) It was raining here today.
Thread Starter
Burning Brakes
Joined: Oct 2005
Posts: 999
Likes: 7
Is this the post you mean?:
The way the shielded cable was intended (I believe) to be attached is there's a microswitch mounted to the side of the radio frame mount which opens/closes the switch depending if the radio is "in" or "out". The inner green conductor wire is connected to one side of the switch and the outer shielded cable is connected to the other side of the switch. In addition to the inner green being isolated from any electrical ground on the car it should also be isolated from the outer shield of the cable.
Thread Starter
Burning Brakes
Joined: Oct 2005
Posts: 999
Likes: 7
The key didn't turn it off. The fuse seems to be inside the alarm module which is mounted well behind the passenger side trunk hinge. There does not seem to be a fuse for this in the fuse block under the hood. I did pull fuse # 12 (central locking system) but that did not work.
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Burning Brakes
Joined: Feb 2003
Posts: 985
Likes: 1
Hi Darth,
Is this the post you mean?:
Yep
"In my case the radio is long gone and the green wire still has the factory connector on the end. I don't think it is shorting. Am I missing something? "
My radio was long gone too. PO just cut it off and let it dangle. The inner conductor was either shorted to the outer wire shield and/or to the chassis of the car which was setting off the alarm.
If you've checked with an ohmmeter there is no connection from the center conductor of the wire to either the chassis and/or outer shield then you've eliminated this possibility. Try disconnecting door switches one at a time or if you're handy with a meter check that they're intact.
Is this the post you mean?:
Yep
"In my case the radio is long gone and the green wire still has the factory connector on the end. I don't think it is shorting. Am I missing something? "
My radio was long gone too. PO just cut it off and let it dangle. The inner conductor was either shorted to the outer wire shield and/or to the chassis of the car which was setting off the alarm.
If you've checked with an ohmmeter there is no connection from the center conductor of the wire to either the chassis and/or outer shield then you've eliminated this possibility. Try disconnecting door switches one at a time or if you're handy with a meter check that they're intact.
Burning Brakes
Joined: Feb 2003
Posts: 985
Likes: 1
In my situation if I remember correctly (i.e. its been about 10 years) I had no issues with the battery going dead unless I had left the alarm to sound but, I likely reset the alarm after no more than 12 hours as it was a daily driver and that was the maximum amount of time it was left unattended. I believe once the alarm is set it will remain armed until the condition is reset. In my case the green wire was an intermitten condition set off typically on windy days when somehow the wind would enter the cabin and disturb the wire dangling under the dash.
Advanced
Joined: Jul 2009
Posts: 52
Likes: 0
From: carmel valley ca
reply
The alarm unit is a blue plastic box about the size of a cigarette pack located close to the firewall, passenger side, probably behind the glove box - access with the hood open. My mechanic had some difficulty fishing it out - it unplugs. As I recall after he dried out the circuitry, the horn stopped but in less than a month he had to resort to replacement. I don't remember the cost but it didn't seem too shocking. The original problem was intermittent. If the unit is the problem, recommend you seal the new or repaired one in a baggie. Also check the hood margin above the unit for a tight fit.