I think halfpick is on the right track with the 33 relay, i believe there is a 33t timing relay that controls the 33 relay. You want to make sure that the brake sets before this relay drops out. If you open the loop circuit before the brake sets, the car will move a little until the brake stops it, which will make it off level. Usually when this circuit fails thought the car will be HI in the up directions and Low in the down direction empty car. If your compounding is off on this type of controller, you will have to adjust the Rototrol series field resistor to obtain flat compounding. On last thing besides the 33 relay is the FRI relay, it should also stay up until after the brake sets. see loop circuit print.