Thanks everyone for your inputs and suggestions.
I took the shells off both the engine and tender today. I disconnected the Smoke Unit and tested it with my VOmeter for shorts and measured the resistance. I could find no shorts. The resistance measured at 8ohms or slightly higher (no higher than 9ohms). I saw a voltage drop of about 0.5v (17.5 vs 18.0v) when all features were turned on under load (I have an analog VOmeter so it is hard to be exact). I don't have the tools to measure the current draw on an AC circuit. When I ran this steam engine and a diesel engine at the same time, the voltage dropped to about 17.0V.
I then took off the wire nuts in the engine and checked the wire connections. All the wires were twisted tightly. I then replaced the wire nuts and tightened them securely.
I disconnected all the PC board connectors I could get to in both the engine and tender. This included the board in the engine as well as the main board and another board (MUX?) in the tender. I inspected all boards for signs of shorts and the connectors for possible bad connections to the connector pins (none found). I then re-seated all the connectors in their respective boards.
After putting the shells back on, I tried out the engine and tender on my track. The lighting was much better but still has problems.
LIN was on and the lights very bright when I started the engine and it was sitting in neutral.
When I started the engine, the light stayed bright for a while (thought I had it fixed but read on). After a trip around the layout, the light had dimmed (but not as much as before today) and was pulsing (it isn't really a flicker but it depends on your definition of flicker).
When I changed the LIN to off, the light became steady and was definitely brighter than before today, but still dimmer than when sitting still in neutral.
I then turned the Smoke Unit off and the lights went off until I turned LIN on. Then the lights were back on as bright as the engine sitting in neutral (the engine was moving around the track with smoke off and LIN on.
When the engine stops with LIN on, the lights pulse as the engine runs slower and slower. At about 4mph the lights go out. At neutral (0mph) the lights turn back on quite bright.
I'm thinking I have a board problem but I don't have the skills nor documentation to determine which board(s).
It's strange that LIN on/off act differently depending on whether the engine is moving or in neutral.
I'm still hoping I can figure this out with your help, but am about ready to take to a repair shop.
Regards,
LAD
