I know where mine are - in the trash. I just bypassed them. At the PDI one broke and fell in pieces under the bed and it took a month to get fixed under their scum system of warranty, so the next time it happened I just bypassed both of them. Its not like there aren't other things I also have to remember before bringing in the slide, I don't need an interlock to verify me

So I didn't answer your question and I'm sorry, but I honestly don't know. When they broke, they just laid down under the bed with yellow wires dangling. I assume they go on the track somewhere (which is also a Lippert product). Who would have guessed the only thing that has given me any grief are the 3 Lippert systems.