To start with its a amtrak 21917 all wheels appear to be picks ups i dont think its a short and it appears to use a single led to light it up.
Ive tried running it solo with 3 difrent locomotives and get the same results.

I have a amtrak Passenger car with lights but when i have it on the track with a locomotive it stops power to locomotive so it stop. Im using Dc operation any ideas, opinions, etc.