What causes the Vaillant Vivaro engine to overheat?

I have a Vauxhall Vivaro and it has been overheating lately. The coolant level is good and the fans are working properly. What other reasons could be causing the engine to overheat?

I had a similar issue with my Vauxhall Vivaro and it turned out to be a faulty thermostat. It's worth checking and replacing it if necessary.

Low coolant levels can also cause the engine to overheat. Make sure to check for any leaks and top up the coolant if needed.

The radiator might be clogged with debris and dirt, preventing proper cooling. Get it professionally cleaned to avoid further issues.