MTS4

My wife and kids were stranded when her 1992 100CS Avant wouldn't start- then seconds later the stupid car alarm went off. This happened several times and then she gave up and waited for a ride home. I drove down there later and confirmed her story. I did a search here and some mentioned disconnecting the battery for a bit- it worked and the car started.

Now I don't trust it to keep working. How do I disable the factory alarm for good? Doing some searching details were sketchy- but something about grounding out a brown/yellow wire?

Anybody know how to do this?

Thanks