Thanks Rick. There is what I guess is just a lens on the rear end of the tender which made me assume it was an LED.
Rick, You mention "a modified front lighting board". Could you elaborate more on this? Thanks in advance!
LOL - well, basically, take all the components off the current board (including the LEDs), then put new, warm white LEDs on it where the old LEDs were, add resistors off the LEDs, and run wires (F0F, Aux1 and U+) to the decoder. You will need to trace the pads with a multimeter, to make sure everything is properly isolated from each other (except U+). This way, all circuitry is in the decoder (the Mars light should not be a "flashing" light). Actually, what I did for the unit in the video above, is I cut a piece of 0.020" styrene to match the footprint (including slots) of the board; then connected a positive half-bridge rectifier to the clips which contact the driver-frame, at the front of the board, so that I didn't need to run a U+ wire. Used Bondic to hold the SMD LEDs and resistors in place, and ran just two wires from loco to tender.
Rick, Sounds pretty straight forward. If I recall, doesn't that board pick up power when under DC? I presume the traces would need to be "cut" to isolate it? It's been a little while since I was "under the shell" of a GS-4, LOL. As for SMT resistors, did you use 1K or ? Again, thanks....
The driving wheel problem had me thinking. As you said shoveing it back and forth could damage them ........ also I was thinking I will have to be careful about cleaning the drivers. Does anyone out there have ideas about cleaning GS4 (or FEF3) driving wheels ? It is possible to make new centre axle pieces and quarter them but it is fiddly and very time consuming. It will be far easier to not trigger the problem.
There is no problem. Just treat these fine jewels properly and there won't be any issues. You can clean the wheels many ways without abusing them. I would just use the tried and true method of spinning them on an IPA treated paper towel with no load. Of course, the fallback would just be to replace the drivers with a KATO OEM set of upgraded drivers. They are available.