A Hypothesis

This week, my garage door opener got finicky.  Again.  I'm on my way to a solution, though.

I finally have enough data points to ponder that it acts up (opens but doesn't close) only in the winter.  I searched online to see if other people have the same problem, or how to fix it.  They do, but I'm not sure they thought of the right way to fix it.

Suggestion one was to check the sensors to see if anything is blocking them.  Duh.  No, nothing fell between the sensors in the 30 seconds since I opened the door and backed the car out.

Suggestion two was to check the battery in the opener.  Duh.  The battery works; that's how the door got the signal to start down in the first place.  It just went right back up again.

Suggestion three was to use the hard-wired push button on the garage wall.  Duh.  That's how I opened the door.  (This is how I've been dealing with it.  I pull my car out of the garage, go back in to use the button on the wall, then exit the house through the front door.)

Then, my moment of random genius hit.  I've been having a similar problem with the remote car unlock button on my key fob.  I thought it might be the fob battery giving out after nearly 10 years.  (I like saying "fob" almost as much as Hobbes liked saying "smock".)  Sometimes, it works with one press of the button.  Sometimes, I have to try two or three times.  Here is the moment of genius:  when do these problems occur?

Incidentally, this post might seem long, but my mother was enchanted once when I wrote her a letter which included my use of the scientific method to test whether the problem was with the light bulb or the lamp, so you should enjoy this.  (It was the bulb.)

The garage door opener always works with the button but sometimes doesn't with the remote.  The remote malfunctions when I'm leaving the garage but not when I'm arriving home.  The fob always works when I unlock the car but sometimes malfuctions when I want to lock it.  What difference is there?  My hypothesis is this:  the battery is cold.

When does my remote not work?  When the car has been sitting in the garage overnight or other long period.  When does it work?  When I've been driving home from work with the heater on, or when it's not winter.

When does the fob not work?  When I've been driving to or from work with the heater on low.  When does it work?  When it has been in the house or my pants pocket (near body heat), or when it's not winter.

I'm going to start experimenting.  I'm going to keep my remote in the house, which is much warmer than the garage, and take it out to see if it works properly even when the garage and car are cold.  I can test the key fob by running my car heater at a higher temperature.  (I'm not sure I can test the variable of why the same car temperature is warm enough for the remote to work but not warm enough for the fob.)

What do you think?