It does not eliminate any problems it only gives data for you to diagnose some problems.
It looks like an interesting tester and could be useful (assuming it works), but everything it does can be done with a standard VOM and a few more standard tools which is why most of these testers are not essential. If an issue is in the ECU, then it cannot diagnose that because it substitutes its internal computer for the ECU.
Its super spendy for what it is, just a novelty. Usually these testers go for more like $250., but the dilemma is that you just don't go down to the store and buy one, so I get their rarity. Highly unlikely it would resale for anything close to that price.
Brad Anders writes about it:
https://members.rennlist.com/pbanders/Testers.htm