Ping Mr Cheerful

Nope; they will be identical WRT voltage, and the larger one will have a bit more capacity.

The numbers refer to physical dimensions in mm. The '20' means 20mm diameter, the '16' is 1.6mm thick, and the '32' is 3.2mm thick. On that basis, the CR2032 is twice the thickness of the CR2016, so make sure it does actually fit before you jam it in.

Chris

Both batteries are the same voltage, so if it will go in then it will not hurt and its capacity is greater, so it will last longer, Duracell are likely to last the longest and you should get at least two years out of one.

so probably a 2020 would go in, while a 2032 would be significantly fatter and depending on the holder might not, all are the same OD at 20mm

Depends on where the battery contacts are. If it makes contact on the rim then it's probably OK. If it's like a Cobra fob that has a metal strap/staple to hold the battery then only the right battery fits, others would be too thin and not make contact to too thick and damage the staple.

It makes contact on the rims. Seems that one is not to make finger contact with the top and bottom of the battery. I do not have surgical gloves.

Thanks for the reply.

That is the theory, but I doubt it makes much difference in practice, you could always use a bit of tissue to handle the battery, just in case.

I also doubt that it makes much difference. Next time I will put a condom over each finger. And my thumb. One must be safe these days.

Sometimes the car gets less sensitive to the fob and the fob user tends to press the buttons longer and more often to get the door locks to work, hence draining the battery faster.

Periodically recalibrating the fob to the car restores the sensitivity.

All the buttons need is a very gentle press. I've saved your link though, thanks.

"The more complicated they make the plumbing, the easier it is to stuff up the drain". Montgomery Scott - Chief Engineer Starship Enterprise.

I find that hard to believe. It's a coded digital signal isn't it. A receiver can't become "less sensitive" to a code. It'll either work or not work surely?

Tim

I don't know about recalibration, but some things have rubber keys which are loaded with carbon to make a relatively high resistance connection across two PCB lands. When the rubber starts to fail, the PCB gets dirty, or the battery goes flat, it doesn't make as good contact and so you have to press it harder to register. Which of course makes it fail faster, and you end up in a vicious cycle.

Theo

Which is an entirely different issue to "restoring sensitivity by recalibrating".

Sounds like the receiver is struggling. No idea where it is. But I'd check it is in the correct place and had a good ground.

I always check the old batteries, they have always lost about 1/2 a volt. Next time I'll get some from a supermarket. With the exception of the two pack from Maplin, they have always been Pound Shop or B&M batteries. Thanks to you and the others for the replies, I've learnt a lot.

How does the rubber failing make the battery go flat?

I had a remote car fob which worked at better range after I opened it up and cleared the fluff out of it. :-)

It's not the nice new clean battery that needs clean contacts. It's the

But I find there are increasing problems with fobs. Places where I have to hold the fob up against the window over the dash where the alarm antenna is. I put this down to mobile phone masts.

I have big hands, the eyes are not to good, but will do this next time. This never occurred to me. Thanks for the heads up.

There are no masts near me.

Done that.

There are overhead HV powerlines carrying data which wipes out all bands on my car radio when I drive past them so might well affect some fobs. Such data is also being fed down domestic supplies now.