Replych530 retros are't sold any more. Sure you don't have an adaptaview? If your com bus is shorted it will not communicate but it should not harm power supply board. If power bus shorts the on board fuse blows. Unplug all buss plugs at the power supply board. Do you have 24v on the output pins? With plugs off com should be up. Plug in one at a time until you loose com. That's the problem buss wire. Work your way up or down the wire disconnecting one at a time until you find the problem LLID. If it is the older flat wire buss have fun. The problem is often in a clamshell. Might be better to rewire with the newer bus with automotive connectors, although it would still need and adapter at each LLID. I don't think there is a troubleshoot manual. If you have access to tech support they can walk you through it.
blast'em man blast'em