Is it possible to get a detailed report from an electrical diagnostic test? on 1995 Buick Regal

After two different shops charged me for 1 electrical &1 trans. diagnostic test. A3rd shop explained to me that my harness is broken and incapable of even plugging into the scanner. I'd like to know how to approach the conversation with the mechanics that took advantage of me.

Only if it was printed out, which a pro. scanner can do. You could go back and request another test and to see it performed. That should not be a problem if it was done the first time. However if you do this and the test is succcessful you will have to pay up! ----Slippery slope.