Corolla Key Battery Issue

I had a similar problem with my older BMW 3 series. The symptoms sound familiar. The key fob would occasionally work, then not at all. Did you try the spare key to see if it's just the one key fob?

Yes, I tried the spare key, and the same thing happens. The 'key battery low' warning appears, and the keyless functions don't work. Do you think it's just a battery replacement, or something more complex?

Since both keys are doing the same thing, a new battery might fix it, but there could be something else. With my BMW, replacing the battery didn't work, so I took it to a workshop. They found the problem quickly. I suggest you do the same.

I took your advice and visited my local service center. Both key fobs needed new batteries, which cost 37€. The technician said both batteries were dead, probably from age and use. Thanks again for your help!