Mondeo Hybrid Overheating

I had similar overheating issues with my Opel Insignia a few years ago. The long warm-up time is also a symptom I experienced. Have you checked for any coolant leaks around the thermostat housing or temperature sensor? In my case, it turned out to be a defective map thermostat. It seems to be a fairly common problem. Does the Mondeo's temperature gauge fluctuate a lot, or is it mostly just high?

Thanks for the quick reply! I haven't specifically checked for coolant leaks around the thermostat housing, but I will now. As for the temperature gauge, it mostly stays high once it gets there, not fluctuating much. Could you tell me more about the defective map thermostat's effect?

Okay, if the gauge isn't fluctuating much, that points a bit more towards a stuck thermostat. For me the defective thermostat was causing the cooling circuit motor to malfunction, it was detected by the on-board computer. I would suggest taking it to a workshop to have the thermostat and cooling system thoroughly inspected. Could be the best approach. Better safe than sorry, especially with overheating.

Thanks again for your input! I appreciate the advice. I'll take it to a trusted workshop and get them to check the thermostat and cooling system, and I'll mention the possibility of a defective map thermostat specifically. I'll share what I learn about the diagnosis and repair. It's probably the thermostat cooling circuit motor defective, which leads to about 350€ repair cost.