my car alarm just keeps going off for no reason....never has done it before, any idea what it could be?

 

hmm after market?

If so it could be the shock sensor is picking up alot of subsonic frequencies, used to happen to mine. A big enough truck drove by and the alarm would go nuts. Try adjusting the shock sensor sensitivity down a little bit.

Another possibility is that you could be having a minor voltage spike running through the car causing the alarm to false.

Try taking it back to whoever installed it and have them take a look at it.

 

thnx, it was doing this as im typing....i went outside messed around with some wires and now it seems to work fine....its locking and unlocking how it used to

 

This doesn't sound right. I think you had better locate the problem rather than just wiggle some wires around until it stops.