i know how to do it for an 02 TL it might be the same.. what u do is take the key.. and put it in the on position.. (the slot before u krank the car up and it sits back after you start it..) hit one of the buttons on the remote turn it off.. do that about 3 more times.. on the 3rd time.. u should hear a noise in the relay system when u hit ur keyless entry button.. when you hear it.. hit all the buttons one at a time on the remote.. and viola.. it's programmed.. i'm not sure if it's the same on the MDX but that's how it works for the 02 TL's