I have a 2011 Honda Fit Sport...... Several months ago, the remote locking system went nuts...... My "unlock" command from the remote(s) suddenly stopped working..... I could still lock everything remotely, just not unlock.... This has lasted for the past 5-months.... Also, instead of automatically just locking the doors once around 10mph, the car would repeat locking..... at least 8 or 10 times..... sounded like an automatic weapon firing..... Also, the car stopped automatically unlocking the driver's door about 2-weeks ago.
I happened to be at a battery specialty store last week... $12 later, the clerk had replaced 1-remote's battery. Of course, this did not immediately fix the problem.... The battery clerk removed battery cable..... then put the cable back on.... BOOM!! EVERYTHING now works like new!! Battery guy said the remote module needed to re-learn the signal from the remote..... Of course I also had to stop at the Honda dealer to get the radio code (my bad)
I explained to the battery clerk that I always could still remotely lock everything no problem... and at about any distance away like since new... He informed me the "Lock" command probably emits less power than Unlocking.....However, every time I attempted to remotely unlock car with a weakened remote battery, I was sending "corrupt commands" to the receiving unit, resulting in its squirrely behavior in general.... Main battery disconnect reset its software.....
It's been working flawlessly now for EIGHT DAYS now! Hope this info helps anyone with similar problem(s).

 

Great post! I will keep this in mind.