Faraday bags work great, as does just wrapping the fob in heavy tinfoil (which is what I use mostly).
I've done this for years with no issues. Even tried an RF scan (I'm an engineer so I have access to goodies like these) just outside the truck. It sees the fob when unwrapped, but not when wrapped.
I've done this for years with no issues. Even tried an RF scan (I'm an engineer so I have access to goodies like these) just outside the truck. It sees the fob when unwrapped, but not when wrapped.