Shaili, I think you may be mixing up a few different things with your question.
The rules vary depending upon various things: whose rules you are operating under, but also whether you are single or two crew. Also are you talking about CAT. I guess you are probably looking at single crew.
You also mention the IR test; this is another special case. When I did my initial test (single crew), you did not use the A/P at all, although it had to be operational on departure. It usually "failed" at some point in the test! I recall someone saying that the A/P may be used for some parts of the IR test these days, but that is just a filthy rumour.