This page shows the internal wiring of the Märklin model 37642. It differs from the other Märklin MaK models in that it has the Swiss light scheme, with three white (yellow) lights forwards, and the lower right white (yellow) light backwards.
Thanks to Bart-Jan Kullberg for the information about the original wiring, and for the photo on this page.
Original wiring
The original wiring of the Märklin 37642 is shown in the figure below. The decoder board seems to be the same as for the 37645 model, despite the fact that they have different article numbers. At least the circuit board is the same.
Figure 1. Märklin 37642 internal wiring.
LED boards
The LED boards are different between the 37642 and the 37645. On the LED boards for the 37642, there are no red LEDs. The lower left and the upper LED are wired together, while the lower right LED is separate. The picture below shows the LED board at the short side of the loco.
Figure 2. LED board for the Märklin 37642. Photo: Bart-Jan Kullberg.
A schematic of the LED board is shown below. The board is shown from the green back side, i.e. the lower right LED is to the left in the schematic.
Figure 3. Märklin 37642 LED board schematic.
Connecting the LED board to the LokPilot decoder
To connect the LED boards of the 37642 to the LokPilot decoder, you will need:
Figure 4. Connecting the LED boards of the Märklin 37642 to the LokPilot decoder.