Ford Focus - steering wheel audio control?

My ';Mr. Fix-it'; boyfriend just swapped out a factory stereo in a Ford Focus (2005) for another. Now the steering wheel audio controls don't work for the new radio. How can we get them to work with the new factory radio? He thinks he connected all the wires.Ford Focus - steering wheel audio control?
All the connections at the back of the radio are conmnectors and should be no wire to wire if there was there is you problem. Another is even thou the connectors plugged into the back of the radio the internal circuit board might not be wired for steering wheel controls. Also let us know what model and year the radio came out of.Ford Focus - steering wheel audio control?
Some radios when changed, computer information has to be removed from the old radlio to be put in the new radio, meaning if you put another ford radio in it, it may or may not work