@Adriatic posted:If nothing is connected, I'd look at.the.track under the truck.
then open it to see if the truck rivet, screw, post, or CLIP is hitting a wire.
Also, too.narrow.a wheel gauge and the backside of wheels may short on turnouts, etc.
I put just the truck on the test track (same one as in the video) and it still sparked. I'm really not sure what to do short of just buying a new truck.