Hi, I received a unit that, when powered on, displays "Autel multimeter function calibrate program". The only button that responds is OK, then it asks: "Input the tool num used: # ". I tried some input, a 3v and short circuit test begins, every time it fails. No menu accessible, I did last update available by pressing left arrow as I power it on, plugged to the PC. Update was successful. I searched on google and through this forum, no answer, please HELP.