The leveling circuit on these cars are a little tricky as you probably know. When coming into the floor the "S" relay must be held up by the actuation of only one of the LU or LD relays. This will begin pre-opening of the doors and "S" relay will remain in until the other leveling relay is energized.
Remember, when the car is level at the floor both LU and LD should be energized. For example, if the car is traveling in the up direction the "LU" relay should energize about 4" below the floor (this will start the pre-opening of the doors if "S" is kept in Properly. Then about 1/2" from the floor the "LD" relay will energize causing the car to stop. At this time the car should be floor level with both "LU" and "LD" energized.
Once the doors close and the car begins to run up to the next floor, The F1 relay should energize dropping out both "LU" and "LD" not allowing the leveling circuit to affect your normal car acceleration. Good Luck!
