This installation of TCS T1 Decoder is for HO Scale Walthers Trainline GE Dash 8-40BW and was performed by A.G.
Here is a picture of the locomotive with its shell on prior to the decoder installation.
Gently remove the shell. The picture above shows the original light board prior to the TCS decoder installation.
Remove the Scotch tape that was originally used to hold the wires together to the light board.
Unsolder all wires that are connected to the original light board as shown in the picture above.
Unscrew two Phillips screws and remove the original light board.
Use the harness that comes with TCS T1 decoder to perform all connections and make sure you isolate all solder points. We used electrical tape in this example. Bridge two, right power pick-up wires and solder them to the red wire of the decoder harness.(as shown in the picture above)
Bridge two, left power pick-up wires and solder them to the black wire of the decoder harness.(as shown in the picture above)
Solder both orange and gray wires of the decoder harness to the motor pick-up wires as shown in the picture above.Make sure you isolate all solder points.
Here is a picture of "almost finished" installation. This engine comes with forward, and reverse lights which is the reason 2 function decoder was used (T1). All bulbs (2) are 12V so no resistors to decrease the voltage are needed. Bulbs used in this locomotive are not "electrically directional" so you can pick one end as either positive or negative. One wire that comes from the forward light was soldered to the white wire of the decoder's harness, and the other was left alone for now. The reverse light was hooked-up in similar way using yellow wire that comes from the decoder's harness. The blue wire that comes from the decoder's harness is the common, positive wire for all lights so all those bulbs wires that were left alone earlier need to be connected to the blue wire of the decoder's harness. We pretty much followed the wiring diagram that comes with the decoder. As mentioned earlier, make sure you isolate all wires' solder points with either electrical or Kapton tape.
All wires were neatly placed under the light board and some electrical tape was used to keep them organized.
Here is a picture of the installation's final step where you can see TCS T1 decoder being fixed with electrical tape to the light's wires so that it does not get into the motor drive.