S80 Brake Light Failure

I had a similar problem with my S80, though mine was years ago when I first got it. Those symptoms sound awfully familiar. Have you checked if the brake pedal is fully returning after you release it? Sometimes, a slight obstruction can keep the switch engaged or prevent it from actuating properly.

That's an interesting point! I'll definitely check the brake pedal travel. When you say obstruction, what are we talking about exactly? Like something physically blocking it, or could it be some kind of internal mechanism issue?

In my case, it was a combination of things. There was some debris that had fallen down there, restricting the pedal movement, and I think I may have been accidentally resting my foot on the pedal slightly when driving. It was enough to keep the switch partially engaged and eventually caused it to fail completely. Given you're getting an error code, it might be worth getting it checked over, I know how tricky some switches are to replace.

Thanks for the insight! I took a closer look at the pedal, and you were spot on! A floor mat had shifted and was ever so slightly pressing on the brake pedal! Removed the obstruction, cleared the code, and everything's back to normal. I can't believe it was that simple, that saved me some money!