First thing that I would do is figure out if it is even putting out a signal. You might be able to do this at an auto parts store that sells "programmable" remotes. I have seen some before where you put the your remote up to their display and hit any button. It lights up to tell you what type of signal it is putting out, there are two different types I believe. If neither of the lights light up then there is nothing else I can think of...