When I fill out the TTax form for federal tax it does not actuate the 502SU in the MD tax. I have been able to get around the same problem in 2 previous years but can't get my military tax reduction to work this year.
You are correct. If there is only one MD subtraction on the form 502SU the form will not generate for mailing a MD return. However, the subtraction amount does happen on the MD form 502 and when e-filing, the form 502SU will be sent. Verify your entries in the steps below.
Next in TurboTax online versions you should see the subtraction amount in the MD Tax Summary using these steps:
In desktop versions you can view your form 502 in the forms mode and look at line 13.
You can also "Open Form" and find the MD 502SU and open it to see the entries there.