No David!
Where it's located and how to access it?
Edit: Found at looked at it, ground was ok.
However, took car to local mehanic, he found out there was problem in comunication between engine ECU amd cooling ECU. Checked out engine ECU connectors, one of them was filled with water, some of pins was turned green - obviously from water from previous washing. Cleaned pins and connector and now everything works fine. 🙂