Question

I'm married but filing separate from my wife. I'm going head of household with my daughter. I pass the test on child dependent care expense but TT says I don't.

Child dependent care credit if married filing separate.

Employee

These are the IRS requirements for your head of household deductions:Requirements.

You may be able to file as head of household if you meet all the following requirements.

You are unmarried or "considered unmarried" on the last day of the year.
You paid more than half the cost of keeping up a home for the year.
A "qualifying person" (your child) lived with you in the home for more than half the year (except for temporary absences, such as school).

You are considered unmarried on the last day of the tax year if you meet all the following tests.

You file a separate return. A separate return includes a return claiming married filing separately, single, or head of household filing status.
You paid more than half the cost of keeping up your home for the tax year.
Your spouse didn’t live in your home during the last 6 months of the tax year. Your spouse is considered to live in your home even if he or she is temporarily absent due to special circumstances.
Your home was the main home of your child, stepchild, or foster child for more than half the year.
You must be able to claim the child as a dependent.

I hope this helps some. If you fit all of the above requirements, go back through the questions about dependents.