04 Trailblazer, Alarm, R/S trouble

what wires did you connect from the rs3 to the 457gw?  did you make your connection to the data wire on the obdII connection after you had Everything else plugged in?  If not disconnect the data output wire from the 457g and then disconnect the 457gw harness.  Let it sit and discharge for 5 minutes.  Then plug it back in and the FINAL step in the install process willthen be to connect the data wire to the obdII connector.  I HAVE had issues with any bypass in these gm's if the data wire is connected before plugging in the interface where the interface wont learn the vehicle.  Neway if you are still having problems try DISCONNECTING the data wire and the passlock connections ( and any other connections you may have had to make with this bypass): return them to their original condition and try starting the vehicle....DOES the security light on the dash still stay on?  Does the dome light operate properly at this point?  If so you can almost for sure pin the problem on the 457gw.  I realize my original post did not offer you any ideas to fix your problem but thats because the problems you are having sound like they are related to the interface crapping out.  The peripheral part i suggested is a one wire connection to the vehicle and eliminates the need to cut into the passlock wires (unlike the dei piece).  One other thing to check...did you connect anything else to the remote starts status output?  If so (and you may not beliieve me but....) perhaps it is backfeeding into the 457g and causing these issues....this can easliy be fixed by isolating these parts from each other with a simple diode( no relay required for something like this)  These new GM trucks are IDENTICAL in wiring and when you have problems like this it is almost always an issue with your interface. 

yeah that'll do the trick