We have just fired up an old system and getting a minor error 2 on an Iwatsu ECS version 5. Any ideas on what this error means?

A minor 2 error means the switch isn't properly licensed, or the 30-day-wide-open-fresh-from-the box license has expired.

What does an error 5 with red light next to maj mean?

The tech manual calls it a 'phase reset error'. Reset the switch and try not to worry too much unless it keeps happening, in which case replace the CCU card.

Thank you for the response. I ordered a new ccu card from Icon, then replaced it, all was good for 2 days, but now i have the same status 5 and the maj red light is on.
Any other thoughts or suggestions?

Clear the alarm with the alarm clear button on the processor and watch it for a few days. If you have any scheduled resets in programming, turn them off for a while. If it continues, get your vendor to get ICON tech support involved.