Bonjour, as they say in France!! How are you all?

Now then. How long does the key fob battery typically last? Does its range shorten as the battery wears down? I click mine on average 10 times per day. Does the battery generally last a certain number of presses? As you might imagine, I'm making sure the car is ready for the winter so am going over it with a fine tooth comb!

Thank You.

I think around a couple of years they should be good for. Of course that might be less if you buy cheap batteries though.

Thank you. I have spent a lot of time researching CR2032 batteries and have concluded that the best ones are Energizer, when purchased from a busy supermarket (never online). I will log how many button presses I get out of them before they go flat. I think it is best to change the key fob batteries every 2 years, to be safe.

GP batteries are usually fine as well, Duracell on the other hand are overpriced rubbish now, Almost every occourance I've had of a leaky battery its one of theirs be it either the copper top type ones or the procell/industrial ones.

Yes, I couldn't agree more! I've been distinctively unimpressed by Duracell batteries during recent years. They used to be the safe bet... now I see them as being low quality batteries that are trading on a once-great name. I hear that Panasonic produce good batteries by the way... I've used some of their 12v gel batteries for other purposes and they have been exceptional.

Hi everyone! So, after 18 months of frequent usage, my Panasonic CR2032 battery was showing a resting voltage of 3.03v.

It looks like lithium ion button cell batteries maintain a very steady voltage over the discharge cycle, so it is difficult for me to tell precisely how flat or otherwise the battery was. But I thought you might like to know.

I am very impressed with my Panasonic button cell batteries. Currently, I am using an Energiser one. I will let you know how it lasts, although I tend to change my battery is every two years whether they need it or not - just to be on the safe side.

Separately, does anybody know where I can obtain a replacement rubber gaskets for the seals of the battery compartment in the key? The rubber gasket seems to be made of very thin rubber and mine has become a bit misshaped over the years, but I would like to replace it in order to ensure that the key fob remains nice and water tight.

Thank you.

An update: I have obtained the data sheet for my Panasonic battery, which suggests that the battery was 40% depleted.

So, by my calculation, I should expect the battery to last 3.75 years absolute maximum, based on my current usage.

By this point, the battery would voltage would have dropped to 2.75 volts (the point at which a button cell battery is typically considered to be "flat" and at the end of its usable life because the voltage then suddenly drops off very quickly).

All in all, looking at the voltage vs remaining capacity curve, I think a sensible point at which to replace the battery is every 2.5 years. This ensures the voltage stays close to 3v and builds in a little bit of contingency before it starts to drop off rapidly.

So there you have it. If you use your key fob quite a few times every day (say, 10 presses per day on average), then the best time to replace a quality battery (such as Panasonic or Energiser), is every 2.5 years - although you can expect it to last up to 3.75 years absolute maximum, before it really does just stop working.

Thank you.

On the case front, this is an option

https://www.ebay.co.uk/itm/124817941991

Just use the bits you need and swap the transponder over (make sure not to lose that bit!)

Only thing I would say, is some of those cases are better than others, some can be made of very stiff plastic. They should be available elsewhere as well, though the few places I found on a quick search the only places with the right ones are eBay and Amazon that I could see.