thanks for the response matthew.
start 'signal' wire for the start relay has to be good or it wouldn't start right?
that's just it, it does start, in ground mode it starts perfectly.
in platform mode it will not start when the service bypass switch is in run mode, but when you switch it to service bypass mode it does start normally.
the path to the starter relay from the tcon is the same circuit in either ground or platform modes.
The difference is the circuits going to the tcon. according to webgpi both circuits are working, the platform signal is coming in to the tcon according to what webgpi shows me.
I know what your talking about and that affects starting overall from either control panel, i had a z135 with that issue before. This one is different.
appreciate your input though. Maybe the genie guy you know can confirm my suspicions about that tcon being the problem.