Well after a little while of trying out different CVs and address combinations, I finally worked out what needs to be done. I have TCS decoders and a NCE Powercab, so if you want independent light control follow these simple steps (see video below for a demonstration):
1. Change CV 49 and CV 50 to 40
2. Remap the ON/OFF Switch to a function key - I chose F1 and F2 for Fwd Headlight and Reverse Headlight for my T Class as an example.
To do this - set CV 33 to 4 and CV34 to 8.
3. Set CV61 to 17 which is the sum of BEMF (1) + Dim when Stopped (16) - so whenever the loco comes to a stop, the lights automatically Dim - The intensity of the 'dim' can be set by
Note: The slight flicker on the Headlight is not perceptible. It is somewhat perceptible in the video because the camera is on a low shutter speed.
The only thing I couldn't work out was how to manually control the DIM. If anyone finds out please let me know (for TCS DP2X Decoders).





