I saw this mower deck engage before I bought it. I drove it 1/2 of a mile after I bought it. I tried to engage the PTO for the deck but nothing happened. I replaced the PTO switch. The deck didn't engage. Power is getting to wire going into the PTO clutch. The seat safety switch lights up on one side. Could it be the seat safety switch? Or, is it more likely a bad clutch? Thanks!