Okay, took the whole assembly off the door. No reprogramming instructions but did find the manufacturer (Alarm Lock, Amityville NY). Checked their web site, what I have looks nothing like what they sell now. (My lock unit is at least 10 years old, probably more). I'll try calling them tomorrow and see if I can get anywhere. They do have lots of downloadable tech. info on their website, but it all seems to apply to their current products.