4L80E No Shift problem

1994 P-30. 6.5 TD Motor Home.

Randomly the trans will not shift after a start. I'm not sure if it is first or second gear (second is default I believe). After shutting down and restarting all is ok. It stores codes 74 and 85. Has done this twice in the past few days. I just checked the codes and they are not there. I did replace the input speed sensor as a stab in the dark and I think the codes were in there before that, but I might be confused. Sorry for the not so clear description. Just thought that this might be a condition that someone has run into.

Bill Carry

Replaced the ignition switch and problem went away.