I was thinking about how to say "I will let you know". The first sentence that comes to mind is
Ich werde dich wissen lassen.
Grammatically this looks fine. However, I feel a bit strange about "wissen lassen". It sounds almost as if I will do something on my side and then you'll know about it (passively). But in reality, I'll be actively letting you know (e.g. by telling you).
Is the sentence correct?
wissen
without an objective, you are referring to some kind of universal knowledge. Then this sentence sounds a bit like Morgan Freeman entrusting Jim Carrey with godlike powers in "Bruce Almighty".