Yesterday, early in the morning, the alarm went off on my vette. It was sitting in the driveway and no one was around. Well last night it did it again. So this time I left it unlocked. Does anyone have any idea where to even begin checking this system out?

 

We had major problems with our 94 alarm system (or so we thought).

We couldn't get the keyless entry system to work right, the interior lights didn't seem to work correctly and the alarm system didn't want to engage, unless we disconnected the battery or pulled a lot of fuses.

It turned out to only be the key bob (the little ball bearing was not moving around to 'wake-up' the key bob) AND the door 'ajar' switches.

Both door ajar switches had failed (i.e. not making contact when the door was opened, but they were springing out fine so they looked ok).

If yours have some water in them, then it could be shorting-out, simulating a door open and a reason to set-off the alarm.

There's a detail procedure in the service manual to remove the switches from the door without taking the door apart, but you could play with them without removing them, just to see if the lights go out or come on and the alarm activiates/deactivates as it should and/or if any water leaks out (they appear to be made quite well, and they are normally 'closed' when the door is open, so the contacts must be near the mounting point, thereby closer to where water could get into them)..

By the way, if it turns out to be the switches, Eckler's has them, but we have gone through 3 bad ones manufacturing defect and sticking, neither were their fault, and they have been great about replacing them for no cost.
:flag

 

you may have hit on something with the switches. I have noticed sometimes that the radio does not turn off when opening the door. This has only happened a couple of times but never the less. The key fob, I never have had with this vette. Ill check on replacing the switches. Thanks for your help!

 

Bingo... I forgot to mention that ours also had a problem with the Radio and windows still operating after the doors were opened (for about 15 minutes -- the normal time-out if you were sitting in the car and didn't open the door), so it sounds like failing 'door ajar' switches might be your problem too. Good luck...
:flag