On Tue, 9 Feb 2016 09:09:04 -0800 (PST), Jc Maxwell
> wrote:

>Somehow the cell that was in the fob was apparently drained enough (measured at 5.03 V) that the fob wouldn't work. When I put in a fresh Rayovac CR 2032, presto, the car again answered to the fob. Must have been a poor-quality cell the first one.
>
>Thing is, I could swear I tried that a few months ago, to no result. I even wrote on the "new-old" cell with Sharpie the words "new cell" so I wouldn't mix it up with the new-new Rayovac CR2032. Oh well, it works now.
>
>Fob response is still not like new though. Sometimes, it takes multiple presses of the button for the vehicle to unlock. Could be the rubber in the fob buttons has become mushy with time and use. Lock and trunk release still work very crisply. The underlying dome switches are still mechanically sound. In fact, the fob innards are in remarkably good shape, for their age and constant use.
>
>The old fob casing, however, is in bad shape, with shackle and a couple of corners chipped off. It turns out you can get a new casing & rubber keys (i.e., everything except the electronics & CR2032 cell) for cheap, so I ordered one.

It's likely that the battery contacts in the fob have some corrosion,
and that is why the remote started working after the battery change.
Try cleaning them.