Why are the renderlayers rendering black? I understand there are a lot of questions similar to this but non of the solutions worked for me. I have a camera, I have lighting, rendering other things worked for me, I've restarted, etc.

Here's the rendered view for one of the renderlayers:

 

Here's the rendered view for the other one:



But when I render:



Black for both of the renders.

.blend:
This is because the Scene layers corresponding to your renderlayers are not enabled:



If you enable the right scene layers (or all of them), then it works as expected.

Note that by default the 3D view layers are linked to the scene layers. You may want to turn this off by toggling Lock Camera and Layers in 3D view > Header:





Also note that there is nothing on the Lines renderlayer; perhaps you meant to select this layer instead?