I have an ‘03 Beetle that I just bought about a week ago, and every night the car alarm goes off randomly for no reason several times. The car is locked and there‘s no sign of anyone trying to get in (plus who would just try over and over again in the same night), so I‘m assuming it‘s faulty wiring or something. Has anyone had this happen to them? Is there some way to temporarily disable it or anything? It was just happening about three times a night, but tonight it‘s been almost constant for about 10 minutes. I live in a safe neighborhood and there‘s nothing valuable in it, so I tried unlocking it in an attempt to maybe get the alarm to stop, but no luck. Any tips for getting it to at least shut up for tonight? Any help would be appreciated.
The alarm unit is slightly to the left of the steering column. It can be removed entirely, and jumpered out of the circuit. Just unplugging the noisemaker won't help because the lights flash and it wears the battery down.
It is lonely and frightened in that neighborhood. Perhaps sleeping in the car a few nights will put it at ease. Or maybe a night-light?
The 3rd brake light in the rear lid is broken and/or loose allowing water to enter the trunk. When water enters the trunk, it runs down the inside of the trim panel straight to the trunk latch, fouling the limit switch. The alarm sounds when the circuit looses the connection because of the corrosion. Open the rear lid, and remove the trim panel. Disconnect the limit switch connector at the trunk latch. You can leave it disconnected, you just won't have a warning light in the instrument cluster when the lid is not shut anymore. The alarm will think the lid is open all the time. The alarm also won't beep when you lock the car, because it thinks the rear lid is open. To repair the problem, replace the 3rd brake light, trunk latch and clean or replace the connector and wire terminals at the trunk latch. You may have to replace the entire trunk lid wiring harness, depending on how bad the corrosion is in the harness. The corrosion tends to travel quite a ways up the harness to other connectors in the rear lid harness. The alarm could be going off for other things, but I think the the rear lid is probably your problem, based on your description.
