[midway78224]

Originally Posted by DonRotolo

The sidecar light says the code is turning the compressor on and off. It is not a problem between the cRio and compressor.
The shorted switch test shows that the switch is not "bouncing" as suggested by Vikingtech2054. Verify wiring is OK by shorting the pins at the Digital Sidecar. If you get the same behavior, the problem is not between the switch and the digital sidecar.

Check (replace) the 37-pin cable between sidecar and cRio. If this is OK, then the issue must be in the cRio

This would mean, 99.999%, that it is your code that is turning the compressor on and off until it reaches 120, which then shuts it off properly.

Try the sample code Jon Stratis suggested, or write your own, but your code is the issue.

It is much less than 0.001% chance, but the cRio or digital module can be bad, but this is extraordinarily rare.

That covers 100% of the possible failure scenarios.

We will try out all this tomorrow at our next meeting. Thanks for all the help.