Thanks so far. I tried with the IGO version that came with the head unit and actually succeeded in changing the resolution. Unfortunately the sys file was accidently deleted and the IGO.sys.apk does not create a new one.
I checked the version when I reinstalled it and it is named 9.18.27.693527
As I understand some apk create sys file and some don't
Is it possible to get access to one that create a sys file?