Chamberlain B4310 learning button
Over the weekend, I installed a Chamberlain B4310 (purchased from Menards if it matters for the model or whatever). All went well and it went up and works great with the wall button provided and the two remotes that were also provided.
That's where the good times end. How on earth do you get the learn button to work? It's round and white. Yes, white. Not yellow (or purple, or any of the other colors) like the manual says it might be(?). Searched the cracks and crevices of the Internet, but no joy. I'm trying to teach a Craftsman 315 key pad, 2007 bmw 3 series and a 2017 Subaru Forester. I might kind of accept that the keypad and even the bmw MAY(?) be too old and not compatible, but I'm not ready to admit defeat and carry the remotes.
Has anyone defeated this mystery? Is there a super secret set of instructions that actually work? Please advise, kind Internet strangers.