458 - HELP HELP - exhaust magnet.

Hi Guys

I have strange issue left exhaust magnet is not working, I have suspicion about the cable has error.
When i flip the cables it works fine. So one of the cables to the controler for vacum it not giving correct power.

I have searched for fuse or maybe it's relay issue somewhere inside the car.

Does anybody have expirence on this topic or have powerdiagram om the wires.