shelby cs 750r siren output

I just finished installed a Shelby CS-750R and when I remote start it, the siren goes off. I read a similar topic with somebody who had this problem but the siren was faint.. my siren goes off completely. The siren output wire shows +12V once the car starts. My question is, could this really be a ground problem? and if it is, why does the siren only go off once the car is started, and not during starting as well? or all the time? Thanks for any input.

never seen a problem liek this before. having the siren go off when the car has started is not normal. If anything, i would say that your brain has some damaged outputs. Or check to see if its your factory alarm taht is being set off.

there is no factory alarm, and even if there was it only operates the horn. I guess I got a dud :(

I further kept having problems with this alarm not sending back the unlock signal and refusing the remote start. Pulled it out and discovered that if the alarm is horizontal, everything works ok but if it's vertical, then the problems happen. I also hear a relay inside when I shake it.. sounds like the metal part inside is swinging around. I'm starting to believe it was damaged during shipping.

Well, I got a replacement unit and still have the same problem. I tried disconnecting the siren from it's ground, and tested it's trigger wire when the car is remote-started. It shows +12V as soon as the car starts. I still have no idea why the alarm sounds the siren once the car starts. I tried disconnecting the tach sensing wire and switching it to voltage checking and it didn't help either. Shelby/Bulldog tech support has never answered any of my 10's of calls.

sounds like its time to pull it out and run over it

that shelby is a real pos imo. I had the displeasure of doing one of those a few weeks ago..I never figured out the siren part so I used the horn.

Other than the bad siren, being incredibly complicated and making it a pain to install, and coming with wires that are too short, this alarm is nice to use when it works. Stars the car nicely and has an awesome range.. There's no way I'm pulling it out.. everything works.. I added a relay to cut the siren on remote start, but it just bugs me that I had to do that.

Oh and I finally got a hold of Tech Support!! Can you believe it ? It's like 10% of the time a human answers and 90% of the time an automated system answers which places you on hold for like 10 minutes then says sorry. The tech guy actually called me after I left a message.. Of course, he knew nothing about it and hung up on me after I described the problem.. ! Never called me back.. Beware of Bulldog/Shelby!