made on the main, where you can hear and see the results of
your changes.
If you are unable to read from the decoder, carefully check
your wiring for any shorts. Use a buzzer to verify that there is
no path from the motor leads to either frame half. Likewise,
there should be no continuity between the trucks and the
frame halves. Check the speaker, too. It should be totally iso-
lated. Check for continuity between the wheels and the rail
contacts on the decoder. Check for motor continuity between
the M+ pad and the M–pad.
If you are able to read and write CVs on the programming
track, then you can operate the loco to the main track and you
should get sound and motion, but no lights, yet. Make sure
the loco goes forward when the DCC system tells it to do so. If
the loco runs backwards, reverse the M+ and M- leads at the
decoder and retest.
12.0 Final Assembly
Let’s get this guy back together. Finalize the motor wiring and
lead dress, if necessary.
12.1 Rebuild Cab
To reassemble the cab, start by hooking the rear light board
assembly over the tabs on the rear lens inside the cab roof.
Then install the rear window set, snaking the yellow and blue
wires through the troughs molded in it for the original contact
strips. Slide the front window set into place. The side windows
snap in place securing the front and rear windows and the gray
LED housing. Some adjustment may be necessary to seat the
front and rear windows so that the side window assembly will
seat correctly and hold them all in place. Snap the cab floor
speaker installation. However, I’m anal retentive enough that I
wire red to the S+ terminal and black to the S- terminal.
10.4 Wire Trucks
Connect the Wire-2951 leads from the trucks to the terminals
on the decoder. If you are going to use this loco on DC, you will
want to observe proper polarity and wire the right hand truck
wires to the left side terminals on the decoder. Since I don’t
plan DC operation, I just ran the wires to the nearest track pad,
as seen in figure 26.
To facilitate the installation of the lights, wire one end of the
remaining 750-ohm resistor to one of the track pads, along
with the truck wire. On the end of the decoder labeled FRONT,
you can choose either side. Figure 26 shows it connected to
the left track pad.
Your loco should look like Figure 26 now. Time to remove the
blue tape that is holding the decoder on.
11.0 Test
You should now have a functional loco, minus the lights. So,
let’s go and test our work.
Go to your programming track. Do not put the loco on track
with full power applied until you verify your installation on the
programming track. If you need a programming track booster
to read CVs with your system,
make sure it is in place and functional.
Read the short address. It should be 3. Write a different short
address and read it back. If you want a long address, write and
verify it at this time. I like to do this in DecoderPro and create
a file for the new loco at this time. Then future tweaks can be
DCC Impulses column - 16
MRH-Jan 2013
