the viper has a digital out that connects to the CANbus interface, that sets the PID active high when the car is about to remote start. when the key is inserted , the canbus goes to sleep till the next wake event from the viper. im not 100% on the viper , but surly there is and valet/override switch in the system if it faults the hardest thing would be to find the PID that's the PATS value (need an insider at ford to help) (may already be known)