There was a Kone job in California that was running, being serviced by an independendt elevator company. Then two representatives from Kone showed up on the job. The next thing that happened im chronology is that some encoder wires got swapped, and the unit can't run at all like that. The independent service company swapped the wires back, and the unit ran once again. I'm not making any allegations here, just relating story the way I heard it from the mechanic