this one is being a real pain in the ass, replaced all the relays in that were in the safety circuit, and it ran for a week and started getting 17 errors, cop stop switch opening, strange thing is that it shuts the car down, it has to be reset as the motion excuse said no more retries 17. so anyway we decided to jump out the cop stop switches to see if was just the stop switches or trail cable. car runs for a week with no errors, then we just stop by to check on the errors, and car is running, but it has a bunch of 18 errors, 10 to be exact, however car is still running. so I'm scratching my head now. we leave it run and now it is shutting down every other day or so with motion excuse of 18 no retries left. this one has me stumped. going to try the msu board next, ill take a look at hoist way switches greg, car is always floor level, never occupied, I'm thinking maybe the M contactor is somehow not dropping sometimes. maybe pr relay is sticking in, I'm going to try and simulate that and see if i get the error.