Hi,
I’ve been racking my brain for days trying to figure this out, but my AO doesn’t seem to be working on anything. However, when I view the AO in another view mode, it works fine. I have no idea and I’m beginning to think the editor is bugged and I’ll need to start a new project 
Here are my two views.
Ambient Occlusion exists as a way to occlude indirect lighting, only as a cheap small-scale effort to simulate the effect of bounced lighting being unable to reach occluded areas.
Therefore AO only affects ambient lighting - it doesn’t make sense to occlude light that is directly affecting an object.
try looking at the effect of AO on dark/shadowed areas that are only lit by ambient light (skylight)
I found a solution that worked for me. Check de box “Ambient Occlusion Static Fraction (AO for Baked Lighting)” in project settings.
