I have several UCS tracks that need to be rewired. Or should I say, the controllers need to be rewired. I followed the example of one that was already wired and soldered a new four conductor set of wires to it. While the unload button activates a cars unloading mechanism perfectly, the uncouple button only gets a weak response and will not draw the uncoupler plate down, on the bottom of the truck.
For some reason my brain is getting the proper order of the four wires. Here are some pictures of the existing controller. Notice the order of the wires. If you flip the controller over, the left most wire would be the one that goes to the far left screw on the UCS track. For some reason the magnet on the track is not getting a strong signal.