Does anyone know what pins are used for the Serial Port interface on the Flash II ECM are (Data+, Data-, Return). I know they are D10, D11, and D12, but which one is which? I have a new unit I just installed into an '89 Corvette (it's TPI, so I have the Port Mod, if that matters), and it won't communicate with my laptop. Any help or ideas would be greatly appreciated.