Nissan Note start stop problem

Sounds familiar. I had a similar problem with my 2016 Opel Astra. The eco mode kept throwing errors. Have you checked the battery's voltage? A heavily discharged or defective battery can cause the start-stop to act up. It's like trying to run a marathon on an empty stomach; the system just can't handle it.

Interesting! I haven't checked the voltage myself, to be honest. Where exactly should I be checking that? And what kind of voltage am I looking for? Is it something a complete novice can handle, or am I better off taking it to a professional?

You can check the voltage with a multimeter across the battery terminals. A healthy battery should read around 12.6 volts when the engine is off. However, if you're not comfortable with it, it's probably best to take it to a workshop. In my case, the Astra needed a new battery, and the workshop confirmed it with a diagnostic tool. Save yourself the headache and potential mistakes!

Thanks a bunch! I think I'll play it safe and book it in for a check-up. Turns out you were spot on, cost me 290€ to replace the battery. At least the annoying warning light is gone and eco mode is back up and running.