alarm siren won't stop! rrrrrgh

[POS carb]

Damn it I have an Alpine alarm, SEC-100 model

Today I noticed the siren didn't chirp when I locked up at work. Everything else still worked, the lights flashed and the doors locked. I passed it off as a bad ground on the siren wire
When I got home today I noticed the siren WAS actually working, in fact it was sounding very faint and won't stop period. The only other time I've heard the alarm sound like this was when I was hooking it up and the brain's ground wire wan't connected. I tested the brain's ground wire, it's good, I even ran an extra... when I disconnect the ground wire it actually gets a little louder but in the end the damn thing won't stop

I tested the siren by applying 12v to the siren's signal wire and it sounds full throttle so I know it's good, however the wire coming from the brain has a constant 1.7 volts
When I arm the system the voltage drops do about .5 v at the wire whenever the lights flash. I tried disconnecting the parking light trigger lead but the alarm keeps sounding

Right now the alarm is hooked up directly to the car's built in relays for lights and locks, no internal/external relays are being utilized. Everything worked 100% fine until today and I can't think of anything that would cause this.

Any ideas before I :pc: the car?

<edit> the fuses are fine <edit>

[zero.counter]

A dirty or bad ground from the alarm's relay perhaps. Scuff the ground area some more for a cleaner contact and put back into the opriginal configuration.

I had that problem with one of my long gone 240s and an alarm. It was faint and sounded like it was dying one day. I checked the relay and even replaced with a bosch from autozone. I cam to find that the ground I had from the relay had corrosion since it was just outside of the firewall. I sanded down a bit, reconnected the ground, and it was back to normal...

[MrBen]

I have those kind of weird problems when I have a corroded or loose connection on my alarm. Funny things happen like the alarm will suddenly go off when I'm on the freeway or it will arm/disarm itself when it's feeling crabby.

[POS carb]

ok more test results...

The alarm has 1.80 volts to the siren now... this should be 12.00
The ground wire for the siren is supposed to be chassis ground and it is and it is fine b/c direct + battery to the red siren wire makes it sound full-tilt

The only way to shut up the alarm is to disconnect the main memory power (constant). Disconnecting the negative while leaving the positive connected makes it ring a little louder but still very quiet

When I set off the alarm (panic) the volts @ the wire drop from 1.80 to 0.80

The voltage at the brain's + and - are 12.7 so that is perfect there...

I'm guessing the damn brain got cooked, hopefully there's an independant little fuse or something inside for the siren

[DanLXI88]

I have those kind of weird problems when I have a corroded or loose connection on my alarm. Funny things happen like the alarm will suddenly go off when I'm on the freeway or it will arm/disarm itself when it's feeling crabby.
:uh: :lol: :rofl:
Going off on the freeway? :lol: Ever get pulled over because of it ?

[TJ89Accord]

sounds like the brain is cooked.make sure there are no shorts or anything.

good luck

tim

[POS carb]

funk itI'm going to strip the car and rewire it today... if that doesn't work then I guess I have a real nice keyless entry system... I still haven't tested the horn honk output, I never hooked it up...

having the alarm go off onte highway means that the yellow wire has a bad connection b/c this is what signals the alarm that the car is running, check that out... If anything tap a new wire to your radio fuse or something