So I have been restoring my girlfriend's mom's lawn since spring. It has come along way since then.

Previously the sprinkler system did not work at all and hadn't been used for at least 2 years. I got it working and started on a liquid fertilization/ weed control cycle and over seeding, most of the lawn has come back quite rapidly since starting this.

I still have quite a few trouble spots not are not filling in at all. In spots throughout the lawn I am discovering moss, I think, growing while other spots are barren with spotty grass patches.

What could be causing this and how can I repair these spots? Am I simply over wattering?

Background info:

In Utah, the grass is a mixture of different strains. I have been sending with Kentucky blue grass.

I have 4 zones each zone has about a 10-20% over overlap. Cycle starts at 5 am for 11 minutes each zone. Heads are your standard 1.5" pop ups orbit 360's and 90's.

The yard is a sun/ shade mix, shade in the morning and sun till dusk.

Pictures: http://imgur.com/a/10dHE

Edit: here's a picture of the whole yard http://imgur.com/5WZU5HX the right side is to the west. FYI the left side is still not mowed. The right side is where is has filled in the best, super thick and green . Towards the middle is where I am having the bulk of the issues and off to the left.