Nissan Interstar Overvoltage

Wow, that sounds like a real headache! Overvoltage issues can be tricky. Have you checked the battery's voltage when the car is off and while it's running? Also, any chance you experienced a power surge recently, maybe during charging? Alternator failure is less likely on an electric vehicle, but still worth considering. Let me know what you find!

Thanks for the prompt response. I've tested the battery voltage, and it seems to be within the normal range when the vehicle is off. However, I haven't tested it while the engine is running. How would I proceed with this test on an electric vehicle, and what values should I be looking for to identify a potential issue?

Okay, testing the voltage while 'running' on an electric vehicle is different than a combustion engine. Given the complexity and the range of system failures you're experiencing alongside overvoltage errors, and especially since you've already noticed a weak starting battery, it honestly sounds like you could have a battery issue or a larger electrical problem. I strongly suggest taking it to a qualified workshop; they can properly diagnose the system and prevent further damage!

Thanks for the advice. Based on your recommendation, I took the vehicle to a certified Nissan workshop. The diagnosis confirmed a heavily discharged and defective battery, which was causing the overvoltage errors. The repair, including a new battery and associated labor, amounted to 290€. Your insights were very helpful in guiding me towards the appropriate solution.