US Patent 10068402 Upgrade kit for an ignition key and methods

One variation of an upgrade kit—for an ignition key corresponding to a vehicle and including an immobilizer transponder and a keyless entry transmitter—includes: a wireless jammer configured to interfere with wireless transmission from the immobilizer transponder; a wireless receiver configured to receive an unlock request from an external device; a relay configured to actuate the keyless entry transmitter to unlock a door of the vehicle in response to the unlock request; and an enclosure configured to contain the wireless receiver and a portion of the ignition key.