wrote in message
oups.com...
If you lose all three transmitters when you program one, they are not
being programmed correctly, probably because the directions are
confusing. (Some Chamberlain directions say to push & hold the smart
button & then push the transmitter button) If you do it this way you
will probably erase the codes. There is a LED light beside the smart
button. If you push & hold the smart button (approx 10-15 sec) until
the LED goes out you have erased all of the codes. To program the
transmitter push the smart button momentarily (LED lights solid), let
go of smart button, push the button on the transmitter within 30
seconds before the LED goes out, (LED will blink once). Transmitter is
coded & you haven't affected any of the other ones.

DoorDoc
www.ActionDoor.com

THANK YOU. THANK YOU. milady was able to program three units today and not
lose the program on the old working one. a copy of this is printed and
attached to the opener

Karl