My pto will not engage how do I check if relay or switch is bad? I checked at the plug for the clutch and I am not getting power.

You can "jump" and see if you hear a click sound at the pto. Jump across connections at the switches wiring connector. Use a test light to i.d. which is the hot, then start jumping in a matter of elimination. If you purchase an electrical part, I do not know of any retailer that will take back an electrical part.