Our body shop is working on a 99 328i conv., we had an upholstery shop install a new top cover. It came back to us inoperable. This is a power top. The L.E.D. on the switch is flashing, I'm told that this means that there is a problem. I was told by a BMW service tech. to disengage the motors using the emergency release under rear seat and manually stow the top. We re-engaged the motors, still nothing. Apparently, the top shop may have tried manually manipulating the top without disengaging the motors. I have a feeling that something is out of synch but I'm not sure what to look for. I have a wiring diagram that shows possibly a pair of top position switches, don't know where they are. I'm trying to avoid having to take this to BMW. Any advise would be appreciated, maybe something obvious we should look for. The top worked before we sent it out, now I'm seriously frustrated.