MAF and oil level sensors not working

[Kelz]

Hello everyone,
I recently got a BMW 116i N45 from 2005.

This is my first Bimmer and I'm currently fixing all the minors oil leaks on the engine.

Also, many error codes appeared on the Carly diag. I managed to delete a lot by just changing the battery. Only two codes remain : one for the oil level sensor and one for the MAF sensor.

I've changed both sensors but the error codes are still showin up.

According to a diagram I've seen, it looks like these two sensors are connected on the same fuse, so I guess something's wrong with the circuit.

I took the car to a BM dealership and they just said that there's no ground signal on the related pin of the DME, so they can't help. I precise they tested this with no fuse in the fusebox of the DME, saying this I literally understand nothing to electric circuits..

Before changing the DME, I was hopping to find some help. Maybe someone had the same issue and could help. I'm feeling a bit lost with this case..

Thanks a lot !