Back to this thread after starting it some time ago - yep, more battery issues!
We were hooked up with the fridge running and after a couple of days the fridge was shutdown along with other items and voltage below 12. Had to take the van on a long drive, batteries charged back up so survived.
Went into our new dealship and they say that it is an issue on the 7.5 ring and this time it’s the rear cupboard light (last time it was the gas ignition). More than 8 weeks later still no part and have escalated to MB. Dealer now says it was an IT issue and they have now actually ordered the part. Regardless they have left us with a vehicle that only powers the 240v socket when plugged in and the 7.5 fuse is in a blown state. So when we go anywhere we need to drive around as much as possible to get the battery charged to keep things like the fridge running. Gas ignition, lights, etc., not working.
When hooked up it says it is charging, the console shows the charge bars moving up, but it does nothing.
Bar getting this new part anyone got any other ideas, I read above about the relay, fuses, etc., but not sure which to try or to hit the incapable dealer with?