As long as you have two-way wireless communication (which any keyless entry/start system does), then you can simply do a Diffie-Hellman key exchange during the pairing process.
Diffie-Hellman is designed for exactly this usecase, allowing two parties to derive a shared secret key over a public channel without exposing it.
As long as you have two-way wireless communication (which any keyless entry/start system does), then you can simply do a Diffie-Hellman key exchange during the pairing process.
Diffie-Hellman is designed for exactly this usecase, allowing two parties to derive a shared secret key over a public channel without exposing it.