So my 320D ate a swirl flap and died on me. I have swapped the engine over with another identical one but I think I have wired up the starter motor wrong.

if i Disconnect the Live wire in the engine bay on the drivers side, I can put the negative terminal on the battery and the car operates as normal.

If I connect the live wire in the engine bay, and put the negative on the battery, it sparks like a live wire would.

If I disconnect the 13mm nut on the starter and take off the two cables it attaches, then I can plug the engine live wire on and place the negative terminal on the battery with no sparking.

From this, I guess it has to be something to do with the starter motor or alternator, Does anyone have a picture of their starter motor and the cables around it so I can compare it to mine, or a wiring diagram of some sort.

I have found

Image Detail for - BMW E60 E61 520d alternator - starter motor base B+ cable NEW ...

But I need more info really.

Thanks for your help, Aidan