[amsat-bb] Icom AG-35 Preamp Question

I bought an Icom AG-35 preamp about a year ago. The fellow ham advertised it as virtually brand new and it was/is. I planned to use it this summer with a TS-2000 which doesn't supply 12v voltage to the coax to power a preamp as other xcvrs do. I used a Mirage KP2 unit to inject power to the coax to drive mast mounted the preamp. When I turn the power on there seems to be little or no noticeable difference in background noise and worse than that I cannot here any signals on FO-29 downlink, and I know the bird has been active. Any suggestions? Is the preamp fried? I can't even get the weather proof case off to trouble shoot, not that I'd know what to look for. Any suggestions on repair?

TNX 73 Rick W2JAZ