I should qualify for the Michigan Homestead Property tax credit but turbotax says I don't. Household resources under $50,000. Paid $1185 property tax. Value under 90000.

I put in those numbers and got a 711 Homestead Property tax Credit on my Michigan return. 

Which TurboTax Program are you using? If Desktop, have you updated? 

(Click "Online" found on the top left of the screen and then click "Check for updates" on the drop-down, you'll need to be connected to the internet to get the updates.)

Did you get the screen shown below and did you check any of those boxes?

Did you get to the "Homestead Property Tax Credit" screen which asks "Do you want to review your homestead property tax credit entries?" and click YES ?

Did you then go through the interview?