The invention comprises a wireless electrical interface system and method for establishing a non-intrusive interface with the vehicle's electrical subsystems required for the operation of an aftermarket electrical device, such as an Ignition Interlock Device (IID) or a GPS tracking device with integrated immobilizer technology. Said non-intrusive interface is established through utilizing engineered connectors for electrical connections to the vehicle's electrical system, and by incorporating wireless interface technology to establish a wireless electrical interface between the vehicle's electrical subsystems accessible only within the passenger compartment and the vehicle's electrical subsystems accessible only within the engine/trunk compartment, eliminating the conventional hardwired electrical interface between aftermarket electrical devices and the vehicle's electrical system.