Audio Systems: Car audio output protection, fm radios, amps

Question
Modern auto AM/FM radios have connections for 4 speakers i.e.
2x front & 2x rear. Is it possible to leave some of these
unconnected/open without doing harm to the internal audio
output amps?
That is, are they protected against no-load conditions?

Thanks


Answer
I've never had a problem doing this, just make sure they're taped or capped off so they cant get against anything.  I have 3 cars with a system in each one and in all of them I have amps for all speakers,  I never use the speaker outs on a cd player unless I can avoid it.
I've done several systems for friends where I used amps for all speakers as well and they never had a problem either.
Good luck and let me know how it goes.