Does it work properly when it is programmed to open only one door? Maybe that will solve your problem.

Don -- I gave that a try, and thought it was the problem. I thought *maybe* pressing button 1 was also pressing button 2.

But, no. I deprogrammed door 2 and button 2. But Button 1 opens Door 1 and Door 2, now seemingly all the time. It's like they've gotten on to the same codes, even though surely that's a 1 in 1mil happening.

Follow-up, FWIW.

Called HomeLink. The trick is to reset the opener itself, not the remote or the car. Apparently once a button is programmed to activate an opener you can't deactivate it except by resetting the opener--reprogramming the Homelink button won't solve it nor will resetting/clearing the Homelink unit.