If you have NEVER taken the radio out before, then if you do you will activate the anti-theft and you will really have a great time finding someone with the tools and codes to reset it.

If you have taken it out and the anti-theft was not replaced then you should be ok. I think the anti-theft is on the right hand side (Passenger) of the radio. If it is connected do not touch it.

Take it back to the AC Guy. Jack M.