Engine disabling

Vehicle engine disabling apparatus comprising,

• a first terminal for receiving an alarm output signal,
• a second terminal for connection to a horn relay,
• a common terminal,
• relay means having a winding with first and second ends and latching and at least one other set of contacts,
• a power terminal for receiving electrical potential from a source thereof connected between said power terminal and said common terminal,
• said first end of said winding connected to said power terminal,
• normally closed reset switching means for selectively interrupting current flow to said winding.
• means including a first unilaterally conducting device for coupling said second end of said winding to said first terminal,
• means including a second unilaterally conducting device for coupling said first terminal to said second terminal,
• means including said latching contacts on said relay means and said reset switching means connecting said common terminal to said second end of said winding for maintaining said relay means operated in response to the occurrence of an alarm signal on said first terminal until said reset switching means is open.
• said first and second unilaterally conducting devices being oppositely poled so that said first unilaterally conducting device prevents said second terminal from receiving a horn relay operating potential and said second unilaterally conducting device prevents operation of said relay means upon the occurrence of a potential on said second terminal for operating a horn relay produced by manual actuation of a horn switch by a vehicle driver,
• and at least first and second output terminals intercoupled by a first of said other set of contacts for connection to a vehicle engine electrical system for disabling the vehicle engine when said relay means is operated and allowing operation of the vehicle engine when said relay means is not operated.