Thought this would be useful info in case someone else runs into this problem. We have a Lionel UP Berkshire purchased about 3 years ago as part of the UP Freight set. We took it out to operate at Christmas in 2008 and it wouldn’t run with the smoke unit turned on. The controller light flashed indicating a short. I assumed the smoke unit had burned out. Finally took it apart last night and discovered that the smoke unit works fine with the boiler off. The top of the smoke unit was shorting out to the underside of the boiler. There is an insulating washer but it was not thick enough. I added another insulating washer and now it works great. It also was tending to stop on switches due to bad electrical contact. I found the the the wire from the trailing truck to the body was broken. We are now back in operation
Welcome to the fourm.
Is this a small Berkshire (Polar Express size)or a big Berkshire (scale)? I don’t remember without looking the set up.
This is the small size.