I have a 2015 X-Trail (T32 1.6DCi Auto) which is often, but not always, coming up with a Stop/Start system fault warning on the dashboard when starting up.
So far I have changed the battery for a new start/stop compatible one for this model (so the shop says), and bought a charger to make sure it was fully charged. Still getting the same issue though.
Sometimes if I go for a motorway run, next start up it will be ok, and may be ok for a few drives, but then comes back again.
I did get my local garage to do me a favour and put their computer on it. That showed lost of Voltage errors, and once cleared it was ok for maybe a week or so.
When I tested the voltage on the battery with the engine on and off, it does seem like the alternator is working. From memory the battery was 12v off load, and 14v when engine running, so I assume it is being charged ok.
Before I take the expensive step of a Nissan dealer for diagnosis, has anyone got any other troubleshooting steps?