^ Actually, that write-up still includes actuation of the garage-door opener's "Learn" button (step 5), which is necessary if the HomeLink device fails to pair when using the remote.There is actually an even easier proceedure on here somewhere that I used. You only use the learn function on the mirror and your remote, no ladder required. Google is your friend... https://www.autonationsubaruroseville.com/research/homelink.htm
That's identical to the behavior I mentioned for mine above. The electrical system has to be powered up for it to work...engine status doesn't matter.I double-checked. The Homelink in my 20 Touring works when the car is running, or not running in acc or on positions.