Swapping the Battery in the Polestar 2 Key Fob

Around October I noticed that one of my key fobs was not reliably unlocking the car. When that happened, I would just use the Polestar app to unlock the car and all was well, even if that was slower.

I switched key fobs when I got home and didn’t think much about it. Until the December and January cold hit and I was again having trouble unlocking the car.

The phone app would still work to unlock, but the key fobs were hit or miss. This is somewhat ironic considering all the phone app and digital key troubles I had early on.

Obviously the key fob battery is the first culprit to consider, but I had changed the battery in one of the key fobs when I got the car and now it seemed like both of them were failing. Should this happen, the manual says there will be a low battery icon for the key fobs that shows in the instrument panel, but I’ve not seen anything.

Note: These were the large full-size key fobs. Although I did use the smaller activity key fob in the summer, for the winter I’d been sticking with the larger fobs since I am now wearing coats with large pockets.

So I decided I would just change the batteries in both key fobs. They use a standard CR2032 lithium cell battery which I happened to have on hand.

Changing the battery is pretty straightforward and there are detailed steps in the Polestar 2 online manual.

The tiny buttons can be a little fiddly, but the covers came off fine. I did need to use a small screwdriver to remove the battery cap off and also to pop the battery out.

I popped in new batteries and re-assembled everything. In a quick test, both fobs seem to be back to normal and are locking and unlocking the car reliably.

It’s not surprising that one of the key fobs battery died since it was likely the original and about four years old now. But it is strange that the battery I had replaced last April also seemed to have died so soon. I have no explanation for that.

I mentioned the activity key fob above and unfortunately there is no easy way to change the battery in that. The Polestar 2 manual just says:

The battery in the buttonless key (Key Tag) cannot be replaced – contact a service center.

Apparently that battery in the activity key fob can be replaced, but you have to crack open the activity key, breaking its waterproof seal and possibly destroying the shell. I also think the battery might even be soldered in place, so even though getting it out and putting a new one in will be a pain, it is certainly possible.

It might be worth it to go through that hassle yourself rather than paying hundreds of dollars at a dealer for a new key. I have also seen activity key fobs for sale on eBay for much less, but if you did buy another one you’d still have to get it paired to you car which will still require a dealer visit (or OrBit software) and it still might have an old battery that could die soon.

One interesting option I saw on eBay (from Drakkar Designs) is a replacement activity key shell that you stuff the guts of the activity key into. You’ll lose the waterproofness, but it makes it easier to open and swap the battery later. I’ll probably look into this once my activity key battery dies.