Lionel polar express train is stopping on the track, then becomes disabled

SOURCE: My new Lionel CW-80 trans former stopped working

I have had the same problem with my polar express, which i just bought recently. Having to send it to the USA from the UK would be very expensive so i decided to open it up myself. The tamper proof screws were a bit of a problem getting into it. I ground down an old screw driver into the triangle shape to undo them. I then replaced them with self taping srews the same size.
The Problem I found was simple, there is an internal (250V, 8Amp) fuse soldered onto the red wire on the secondary winding of the transformer. The red wire going from the transformer to the PCB, the fuse has black heatshrink over it.
There is no room inside the housing of the controller to fit a fuse holder. I fitted a box on the side of it with a panel mount fuse holder. drilled a hole through the housing, fitted longer red wires, so they could go through to the terminations on the back of the fuse holder.
At least now I can change it simply if it blows again.

hope this is of help to you.

SOURCE: lionel train won't reverse

there should be a switch under or in the cab section that turns off/on the reverse function.

SOURCE: Lionel train power issue

Answer a number of questions:
Is the tranformer power adequate for the train and is it a working tranformer?
Will the train run by connecting the wires directly to the two points of the train (wheels and center rail connector)?
Are the tracks new?
Is the lockon new?

SOURCE: Lionel Polar Express Berkshire Locomotive will only go in reverse

No doubt the transistor in the motor controller inside the engine is shorted TIP31C Q6 If you have the skills you can repair the unit. Parts are cheap, like 50 cents. Expense is shipping. Have repaired at least one that had the probblem you describe
good luck

SOURCE: WE are trying to get our lionel holiday train

There is no on/off switch. Remote will give no indication of working. Try putting engine and coal car only and try. I have had this train set for two years and the remote tends to work whenever it wants.