Nissan Livina Terminal 30 Error

I had a similar issue with my old Opel Astra, although the error code was slightly different. The symptoms you describe, particularly the poor starting and the discharged battery, sound very familiar. Have you checked for parasitic drain? That's where something in the car is drawing power even when it's switched off.

Parasitic drain, huh? Interesting. How exactly did you go about diagnosing that on your Astra? I'm assuming you didn't just stumble upon it. What kind of current draw were you seeing, and where did you eventually trace the fault to?

Identifying the source was not immediate. I methodically disconnected circuits, monitoring the ammeter until the drain disappeared. I would recommend you do the same if you have appropriate equipment. However, considering your vehicle's age and the nature of the fault, it might be prudent to have a workshop perform a comprehensive diagnostic. The cost is approximately 290€.

Parasitic draw was indeed the culprit. After a thorough investigation, a faulty relay in the audio system was keeping the amplifier partially active, draining the battery overnight. Replaced the relay, and the Livina is starting like a champ again! Appreciate the pointer towards parasitic draw; saved me a heap of time and money.