I used to do after-market repair medical equipment (MRI's, CT's, X-Ray, etc). One of the biggest frustrations was: $manufacturer wants $5000 to repair a CT. We'd charge $1000. We'd repair the CT, and it would pass all the built-in diagnostic tests. But then when the customer went to make a scan, a pop-up would appear saying "Unauthorized Repair! Call $manufacturer to fix!". $manufacturer repair tech would come in, pl…
I suspect the liability for medical device mess-ups is at least partially responsible for that situation. The tech who didn't run any diagnostics would be in serious shit if a patient died after he did nothing aside from typing in the error-clearing code on your repair.
In many cases, the FDA requires the device manufacturer to maintain training records and updated repair procedures for any repair shop doing repairs on their devices. This could be the source of that error message.