Steve Walker wrote:

The car fobs that you press a button to operate use a rolling code
system to prevent the recording of a code as it is used and subsequent
playback.

I think that vulnerabilities in the rolling code system have been found
though.

Place a jammer near the car, so car doesn't receive properly, use a
device to capture code n from the remote, user notices car doesn't open,
presses button again, device captures code n+1, disable the jammer, play
back code n, car opens, thief keeps code n+1 for later use ...

car and remote allow a 'window' of several rolling codes, so in practice
thief can capture n+2, n+3 etc codes ...