Ok I went and bought that replacement siren to get the key chirp. This thing does not chirp, it beeps like a microwave. A chirp is that sound that birds, bmw's and mercedes make. So i just wasted 70 bucks for a siren that sounds like crap, and a 35 dollar gear pully that has no other uses.

Reading back on the original thread i see that about half of the people call it a chirp, and half call it a beep. I will have to read into the details next time.