Keyfob battery life

After just over 1 year I've found it necessary to change the battery in one of the smart key fob's for my Prius.

Thing I find a little odd is that this is the 'sorta' spare one, I normally take the one that I have a belt loop thing on it to work with me and the car every day, not this one. So this is the fob that sees less use yet the battery seems to have gone in it first.

Not a big deal, but I did have to hold it up against the car start button to get underway. The car 'saw' the fob coming as the interior lights came up as I approached and the doors unlocked as I pulled the handle. When I hit the power button though the dash indicated that the key was now not detected. There never has been a low fob battery warning ever given, but the car seldom sees this key so again, nothing wrong I suppose. It could have shipped with a weak battery or, the real reason for my post, is this;

Normally I leave this 'spare' keyset and fob on top of the TV set top dvd player that also happens to be the home to the wireless internet router. Is it possible that sitting beside an always powered up router, emiting rf in the 2.4 and 5.8 range is 'talking' to my Prius fob is using the battery up? Or did I just have one with a weak battery. I think the manual suggests something like 3-5 years life on the battery but I really haven't looked at it in over a year now so perhaps my recollection is inaccurate.

Roland.

p.s. bought my replacement battery in a fry's store in Vegas for $1.29, never have seen that 1632 oddball size up here in Canada.

 

Yeah, it seemed possible and plausible to me that the short battery life could have been caused by my decision to keep them in that spot.

Thanks for confirming my suspicions and I'll find a new home for them now.

Roland.