Such lack of detail...
You say you "hooked everything into a mustang 08." What does that mean?
How is it wired up?
Do you have +12v, GND and IGN connected to the appropriate lines? Where do you have each one connected?
Do you have the 2-wire lead going to the power button headers of your Mac mini?
Are you using hte "Mac PAc" cable kit or did you cobble this connection together on your own?
How are the jumpers set on the P2140?
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