I had this problem with my Aveo where about 90% of the time, when I locked the car with the remote, the doors would lock but the car would not beep (signaling the arming of the factory alarm system). The other 10% of the time, the alarm would set (and the car would chirp) but then, just randomly, 10 or 15 min later, the car alarm would keep going off unless I tried locking the car again and didn't get the beep. If you have this problem, it means that one or more of the door switches is bad and is making the car think that one of your doors (or your hood) is open and won't set the alarm. The most common switch to go bad is the one for the hood because it is much more exposed to the elements than the ones on the doors. Attached is a picture of where the switch for the hood is located. To remove it, you have to remove the grille in order to disconnect the switch from the wiring harness. Mine looked a little rotted and had a hole in it and the button felt grainy when I pushed down on it. To check if a certain switch is causing the problem (or as a temporary/cheap fix) you can stick a wire into the two little holes on the plastic end of the wiring harness to close the circuit. If the alarm now arms itself then you have found the right switch however opening the door will no longer trigger the alarm system. The replacement switch from the dealer was only about $8 and took about a minute to install.
A D V E R T I S E M E N T S
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I had this problem with my Aveo where about 90% of the time, when I locked the car with the remote, the doors would lock but the car would not beep (signaling the arming of the factory alarm system). The other 10% of the time, the alarm would set (and the car would chirp) but then, just randomly, 10 or 15 min later, the car alarm would keep going off unless I tried locking the car again and didn't get the beep. If you have this problem, it means that one or more of the door switches is bad and is making the car think that one of your doors (or your hood) is open and won't set the alarm. The most common switch to go bad is the one for the hood because it is much more exposed to the elements than the ones on the doors. Attached is a picture of where the switch for the hood is located. To remove it, you have to remove the grille in order to disconnect the switch from the wiring harness. Mine looked a little rotted and had a hole in it and the button felt grainy when I pushed down on it. To check if a certain switch is causing the problem (or as a temporary/cheap fix) you can stick a wire into the two little holes on the plastic end of the wiring harness to close the circuit. If the alarm now arms itself then you have found the right switch however opening the door will no longer trigger the alarm system. The replacement switch from the dealer was only about $8 and took about a minute to install.
- rgoessl, Aurora, Ontario, canada