Did you have a weed problem that needed to be taken care of? That might cause grass to turn yellow temporarily.

To be more accurate, it's not really yellow,it just isn't growing. light green or almost dormant looking in a lot of areas. There is one section where it is emerald green and looks perfect. But most just hasn't taken off.

shade issues?

How are you watering, mowing and feeding?

hardly any shade, sun is not an issue. The area that is in the shade on our side yard is growing fine. We watered heavily the 1st month and have cut back to 2-3 a week in the second month. I really have not had to cut it, although I have cut it once.

It's just not taking off as expected.

How often did you fertilize? Is that area really hard to poke screwdriver through?

Agree about fertilizer and water. Poke screwdriver in the good and bad areas. Does it take the same effort to push it in? This will give you some clues

Is the turf knitted to the soil so that you can't pull up the pieces of sod? If so then one thing wrong is you are watering too often. At most, for the hottest weeks, you should only be watering twice. If your temps are in the 80s, then you should be watering deeply once every week to 10 days.

Tifgrand is marketed for good shade performance, so a little shade should not be an issue.