NOTE: While this installation demonstrates the use of an M4P-3.5" in this locomotive, we have since added the LL8 to our decoder line. The LL8 is designed to fit the Life Like Proto 2000 series and would greatly simplify this installation.
It is worth mentioning that this is a rather involved installation that uses a 4 function decoder and is not advised to be performed by beginners.
This installation documentation is for the HO Scale Life Like Proto 2000 GP38-2. This installation uses the M4P-3.5" decoder, and was performed by A.G. and N.G.
The pictures above show the locomotive prior to the decoder installation.
Unscrew the front screw (already removed in the picture) as well as the back one that holds the coupler pocket to the chassis and remove both coupler pockets.
Grasping the shell by the solid area between the grills, lift the shell straight up and off of the chassis. The picture above illustrates the original light board with the DCC-ready plug. Lift the DCC plug up to unplug it and unscrew the two screws that hold the original light board to the chassis.
Unscrew the DCC board as shown in the picture above. You can see the pin numbers on the bottom of the board (P1, P2, P3, P4, P5, P6). If you are using a LL8, simply plug the decoder onto this plug. If you are using the M4, follow the steps below.
Remove the black plastic coverings and de-solder all the wires that attached to the DCC socket board. Because of the fact that this locomotive uses 4 different lights (forward headlight, reverse headlight, and two number board lights) a four function decoder needed to be used. The space is very confined so we decided to use our small M4 with a short harness (M4P-SH). The voltages of the bulbs that came with the locomotive are not identified in the locomotive manual, so we replaced them with 3mm LEDs. Remember to use a 680 ohm resistor in series with every LED. Here is the pin configuration for this installation:
Pin 1 (P1) - Red motor wire (thick red wire)
Pin 2 (P2) - Reverse headlight
Pin 3 (P3) - unused
Pin 4 (P4) - Black power pick-up wire
Pin 5 (P5) - Black motor wire (thick black wire)
Pin 6 (P6) - Forward headlight wire
Pin 7 (P7) - Common pin for lights (LED anode)
Pin 8 (P8) - Red power pick-up wire
Green wire (from the decoder) - Forward number board lights
Purple wire (from the decoder) - Reverse number board lights.
One side of the 680 Ohm voltage limiting resistors that are used for every LED should be soldered to the LED's cathode and the other side should be soldered to the proper pin/wire for that LED. The anode of each LED should be soldered to Pin 7 (Common pin for lights). For more information see the literature that comes with your M4 decoder.
A 3mm LED is too large to fit into the fixture for the front headlight, so we used a surface mount LED (as you can see in the picture above).
Make sure you place some tape under the original DCC plug (kapton tape used in this example) to make sure there is no electrical connection between the chassis and the board. Insert the M4P-3.5" so that the Orange wire of the harness is lined up with pin 1 (P1) of the DCC socket.
Here is the picture of the final installation right before the shell placement. Do not forget to reinstall both couplers that you removed in the first step.
Important Soldering Tip
Please do not use any flux either liquid or paste on the mother board. Over time, the acidic properties of liquid or paste flux will begin eating away at the fiberglass PCB and will damage it. Use only Rosin-core solder or no-clean flux approved for electronics use.
TCS recommends the use of Kester "44" Sn63 Pb37, .015" diameter Rosin-core solder. Kester part number 24-6337-0007.
You can order this solder from the following retailers:
Digikey - PN:KE1110-ND
Techni-Tool - PN:488SO6775
Other solder tips
When stripping wire, only strip a tiny little bit of the insulation. Strip no more then a 1/64 of an inch. When the wire gets tinned with solder, the insulation will shrink back more. Try to not expose any more wire then half the length of the solder pad at most. In no case should solder or exposed wire wire ever be outside the boundary of the the solder pad you are attaching a wire to.
Click here for important information on properly Stripping and Tinning wire