Focus tire pressure loss ABS and steering issues

Sounds serious! The ABS and power steering issues could be linked to the tire problem if the system is detecting a significant difference in wheel speed. You could have a punctured tire. Have you checked the tire itself for any visible signs of damage? Is the pressure loss rapid?

I've checked for punctures, didn't spot anything obvious. The pressure drops noticeably over a day or so. Could it be something like a faulty tire sensor causing all these issues, or should I focus on finding a slow leak?

While a faulty sensor is possible, a pressure drop that significant is more likely a slow leak, especially given the other symptoms. It could be a valve issue. Honestly, with those symptoms, I'd get it checked out by a professional workshop ASAP. Better safe than sorry with steering and braking!

Thanks for the advice! Took it to a workshop, and it turned out to be a defective valve in the tire. They replaced it, and everything's back to normal. Total cost was about 280€ Appreciate the help!