@papajoewill posted:...in my LC2 Big Boy ... Would it be the same diode installed there? Yes
...and where would I be looking to install it? I assume the power pickup area but unsure about "how" to find that inside the train.
The best place to install the TVS diode inside the locomotive is as close to where the Hot and Common wires (from the pick-up and wheels respectively) attach to the circuit board(s). You can either visually follow the wires from the pick-up/wheels or you can use a multi-meter to check for continuity (nearly 0Ω (zero Ohms)) ; first between: 1) the center rail pick-up roller and the circuit board, and then 2) the wheels to the common connection at the circuit board
See my answers above in quote box.
