Saw a tech at a parts counter in Amarillo install a used control board straight from the box, no testing, no nothing | Appliance Repairers - Talk Freely
Guessing he figured the box was the test. That board probably came out of a truck that got fixed with a new one, so it might work fine, or it might fry the whole dash. Either way that customer is coming back and it won't be for a happy reason.