Nissan Multi Engine Overheating Communication Error

I've got a Nissan Multi as well. Your issue sounds familiar. I had similar problems with the check engine light and some weird engine behavior. I didn't have the coolant leak, but it might be related. Have you checked the data link connector and all the wiring harnesses connected to the ECU? Those things can get corroded or damaged over time, especially in older cars.

When you mention 'weird engine behavior', could you be more specific? Did your diagnostics also point towards a control module communication problem, and did this eventually lead you to inspect the wiring harnesses?

By 'weird engine behavior', I mean it was idling rough and sometimes stalling. I didn't have a fancy reader, so I took it to a workshop. They told me something about a faulty connection causing the issue. I'm not super tech-savvy, so I just let them handle it. But if you're getting a communication error, it's probably best to take it to a professional who can run proper car diagnostics. It could save you a lot of time and frustration. Don't risk further damage.

A thorough inspection confirmed a corroded connector on the engine control unit, precisely as suspected. The repair, costing 95€, fixed it. Thanks for the guidance.