Patent ID: 6570486
Filing Date: 2003-05-27
Classification: B60R,G07C

Abstract:
A method for controlling access to a vehicle which has a door and an engine, that method comprising the steps of:(a) periodically transmitting a first interrogation signal at a first rate from a control circuit on the vehicle; (b) receiving the first interrogation signal at a remote control that is separate from the vehicle; (c) upon receiving the first interrogation signal, transmitting a first reply signal from the remote control; (d) receiving the first reply signal at the control circuit; (e) after receiving the first reply signal, periodically transmitting a second interrogation signal at a second rate from the control circuit; (f) receiving the second interrogation signal at the remote control; (g) upon receiving each second interrogation signal, transmitting a second reply signal from the remote control; (h) receiving each second reply signal at the control circuit; (i) measuring strength of each second reply signal at the control circuit; (j) activating a first function of the vehicle when the strength exceeds a first predefined threshold; and (k) activating a second function of the vehicle when the strength exceeds a second predefined threshold.