I guess I just expected it would be an obvious setting but either I’m blind or I’m just lost. Any tips?
The XC40 user manual is a bit confusing on this point. I had to do BOTH steps for Homelink pairing:
1) hold the garage door remote very close while pressing desired Homelink button
AND ALSO
2) press "Learn" button on opener, then within 30 seconds run back to car & press desired homelink button.
The manual implies you can just do step #2 if you know you have a door opener with rolling security codes (eg, if step #1 fails). That's how it worked on my older cars.
Don't know the details - but my guess is maybe since newer Homelink buttons can perform many tasks, step #1 is required to tell Homelink that it's going to be used as a "Garage Door Opener" (as opposed to light switch, gate switch, security alarm disable, etc)? EDIT: or maybe it's just an extra security step.