I coded the new agm battery with ncs expert to 80h agm which was the highest possible one.
today i tested the 18 pin cable which connects to the instrument cluster and there is no power on every single one of the cable. Could it be the micro power module or the kgm?

I coded it correctly and I only coded the cas. and all was well until I replaced the battery. after I replaced the battery the boot light also stopeed working. No power to instrument cluster. What could it be?

It just seems you messed up some where. The key is that the boot light went out so that means something happened during the install. Need to figure out what you fried. If you're not using a towel or something to cover the terminals while installing the battery then more than likely something got touched that shouldn't have. Honestly we can guess all day what it is but since we were not there and can't run tests you're going to have to think logically on how to tack it down. I would start with the boot light and work my way back or check F41 in front fuse holder but if boot light is out I can't see that being the issue. If I was there doing the install I'd know exactly what was touched that shouldn't have been so it would be an easy find

You simply replaced the battery and now you have all these issues? That all seems very odd and is why I am doubting your diagnostic setup. You could be chasing red herrings.

I just need to know why my cluster doesnt get any power

E60 520d M47D2 2005/05 163hp NC31

365.000 kilometers

no power to cluster on the 18 pin cable.

There are many many reasons why your instrument cluster is not turning on. It's not as simple as no power.

We are trying to help you isolate the culprits, but you seem to want to follow your own way.

With BMWs being complex vehicles, fixes are not always simple like with other not so complex cars.

If you need a solid answer an Indy shop would be the place to take it otherwise you're going to have to troubleshoot it yourself by way of us giving you some things to look at. Those are your only choices. No one is going to be able to say "oh it's this", not even a mechanic. You have all the insight of what happened during the install and we can only go by what you have told us.

Ok so I managed to get the cluster running by connecting 12v to pin 9 and ground to pin 18. The cluster is not dead. My suspicion is the kgm and the mpm module which is integrated in the kgm.

You keep saying you think it's a module but still haven't checked F41. I'm not understanding your troubleshooting steps. Your issue is with terminal 30g-f. If you want to just check for power check pin 1 on x16759 (51 pin) to see if it's sending out power. If it is then it's not the KGM.