A fault code doesn’t yet mean the unit or sensor itself is faulty: often it’s the plug and connector leading to it.
Possible causes
- Thermostat stuck open or opening too early
- Temperature sensor
What you can do yourself
- Check the warm engine temperature on the “Sensors” tab.
- Usually the thermostat is replaced. With a stuck-open thermostat the heater blows cold in winter and fuel consumption is high.
The explanation comes from the error code reference in the AvtoElektrik PRO app.