Coolant Loss Check Engine Light

I had a similar issue with my Transit. Check the radiator hoses and coolant reservoir for any leaks. It could also be a faulty cooling fan, causing the engine to overheat and lose coolant. Has the engine temperature been running high?

Thanks for the input. I've checked the hoses and reservoir, and I don't see any obvious leaks. The engine temperature gauge seems normal. Could a small leak still cause this much coolant loss and trigger the check engine light?

Yes, a small leak can definitely cause coolant loss over time and trigger the check engine light. Since you don't see anything obvious, get a workshop to pressure test the system to find the source. It's a more reliable way to spot minor leaks. I had the same problem some time ago. In my case, it was a leaking water pump. I advise you to visit a workshop.

I appreciate the advice. I'll take it to a workshop for a pressure test and inspection. The repair cost was 52€. Thanks again for your help.