My car was behaving strangely recently. Sometimes when I gave it the beans it would pop up a flurry of scary error messages about the engine, that I had to take it to the mechanic to have it checked out and so on.

500 € later and the mechanic could not fix the issue.

Other times, just turning on the engine it would complain that some filter was almost full. And once, on a longer than usual trip, it gave up on me in a pretty steep incline and I had to stop on the side of the road, let it cool down a while, and turn it on again and it worked mostly fine if I didn't accelerate too much.

Then a few weeks ago it did not start at all. So I measured the battery and it turned out it was toast. I had a friend bring me to buy a new one and swapped it in.

The car started fine. But incredibly, it never again displayed any error messages and seems to be completely fixed!

Not really phone related, but yeah, sometimes it can be (surprisingly) just the battery...