Hello John J,
Welcome to the forums! Simple questions are welcome too.
Especially since the SNAP-AITM module is on the "lifetime" list for our warranties:
I'd strongly recommend you contact our product support group, it's free! They can help you determine if the modules are still good and if you did anything to void the warranty.
Just curious -- why were they replaced? FYI, if you were seeing any funky readings coming from the modules, check the voltage on the rack. That's one of the most common issues product support helps to uncover when people call in with module issues. Here's a quick video showing you how to check for that:
Voltage check OptoMinute
Thanks for asking, and I hope you'll share details of your situation and what you learn!