XC40 Tire pressure sensor issue

Could be a faulty tire pressure sensor. Have you tried checking the actual pressure reading from the car's system versus your gauge? Sometimes there's a discrepancy. Does the system show which tire is supposedly low?

The system doesn't specify which tire, just a general warning. Is it possible the sensor battery is just dead? Seems odd on a car this new, but...

Yeah, sensor battery failure is definitely a possibility, especially if it's not indicating a specific tire. Though uncommon, it happens. You'll likely need a shop to confirm. They can read each sensor's status. Expect around 280€ if that's the issue.

Thanks! Took it to the workshop and it was indeed a dead sensor battery. Replaced the sensor, and the error is gone. Cost me exactly 280€ as you predicted.