Alex,
Before taking apart my 2026 which is a last resort. Give me a whole checklist of things to try before doing so. I have followed Lionel's suggestions and believe the lever is in the U-channel correctly. I see the front one move when the engine is turned on and it functions properly. FYI its just the back one. Also I am using a lionel 180 brick through the MTH DCS and TIU and WIU then to my Legacy 990 controller throught the SER2 plug. I doubt that matters but just in case.