C70 emergency call system error

Sounds like a potential wiring issue. Does it happen intermittently, or is it constant? Any recent work done on the car's electrical system?

It's pretty constant. And no recent work, that's what's weird. So it is likely the cable itself?

Likely a defective cable or a plug connection issue like you mentioned. These systems are pretty sensitive. I'd recommend getting it checked out at a workshop, but it shouldn't be too pricey to fix.

Thanks! Had the C70 at the shop, and you were spot on. It was a faulty connector. 95€ later, all good!