Hi, there.
Has anyone out there followed the instructions presented by Con-Cor to install sound in its Aero-Train “DCC Car”? The instructions are linked below:
Con-Cor Instructions
What I’m specifically wondering about is the instructions associated with Photos #44 - #45 - #46. They tell you to:
“Now remove the P3 spade cover on the Wiring harness and place the Green wire from the decoder though the insulated opening on the Wiring Harness marked P3.”
Now, the green wire is already connected into the 8-pin DCC connector, which is already plugged into that extension-cord. That makes me wonder, gee, is there a mistake in the instructions, is this in addition to the contact already made via the 8-pin connector, or instead of?
Basically, should I
-
leave this unconnected for the time-being
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cut it off the 8-pin connector and connect to P3 as instructed
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splice an additional lead into the green (so it’ll still be connected to the 8-pin connector), and connect THAT to P3?
I’m also sending an email to the company, but thought that this has been out for long-enough that SOMEONE else must have asked this question!
If the decoder you are using already has the green wire connected to the 8 pin connector, then just leave it connected that way and don’t worry about the other P3 connection. The decoder they show in the picture does not have the green wire connected to the 8 pin plug(most decoders that I have seen that have the 8 pin plug and more than two functions do not have the green wire attached to the plug) and the P3 connection they have is just an easy way of connecting the green wire to pin 3 without having to solder it.
I guess it is good that I bought LokSound, rather than the decoder they used in their instructions, because the green is properly connected, then, per page 10 of the LokSound instruction manual. Great- gonna go program it, and run it at the train show in Monroe, WA this weekend!
(although I do need to make a little more room for the speaker first, I guess)
At the recent train show in Springfield MA, a rep from a DCC company commented that Con-Cor is rather clueless about DCC (perhaps a bit unkind on his part).
I would contact the manufacturer of the sound decoder (MRC?) and ask them.
The green is comonnly NOT connected to the 8 pin plug on many decoders - simply because it ‘breaks’ the “you can plug it in backwards and nothign bad can happen” design of the pinout of the 8 pin plugs. This is why Con-Cor has the extra attachment point for said green function wire. I don’t think that’s being ‘clueless’ about DCC at all. Now, some other aspects of their design may live up to that, but not this.
–Randy
Actually, I’ve got my answer. The green wire for my LokSound decoder was already connected to the 8-pin plug (another wire, for another output, was loose on this decoder).
I won’t go where that rep went, except to say that… the outputs didn’t seem to match up very well with what I would expect. I had to play around with the function → output mapping to get satisfactory results. I don’t have the exact mappings memorized (that’s what JMRI is for…), but for example, the center red light, which should probably be mapped as either a Mars light or Gyralight, actually responds to turning on function output 0 (IIRC). Normally, function output 0 would be the forward/reverse headlight, but I think that actually responds to function output 2…
I’ve got them mapped fairly satisfactorily right now, at least good-enough to run at the show this weekend. I’ll continue to fiddle with them after that, since it’s the last show of the season. 
Randy, I was thinking about this on the way to work today… the “plug it in backwards and it will still work.” I’m certain that the ConCor extension cable (going from the locomotive into the “sound car”) has a green wire, and my LokSound decoder also has the green wire, AND I’m 99% certain that they all mesh properly at the decoder end. I’ll triple-check tonight regarding whether they all match at the locomotive end of the extension cable; perhaps that’s related to the odd output matching (or, mis-matching) that I described just now?
Gee, if only I didn’t have to work. I’d have SO much more time for trains. Less money, though, so it’s probably for the best. Speaking of which… back to the salt mines!
I know on the N-scale version, and I suspect the HO scale version as well, the center red light and rear backup light are both wired to F0R(reverse) and the headlights and rear tail light are wired to F0F(forward) so that when going forward the headlight and rear red light are on and when going in reverse the front red light and rear backup light are on.
What I meant by the “plug it in backwards” comment is that if you look at the typical pinout of the NMRA 8 pin plug (without the green wire - just red and black, orange and grey, blue, white, and yellow) is that if you plug it in ‘backwards’ - which is easy to do since it’s not keyed in any way - all that happens is the motor power leads get swapped (and the track pickups but since the phase of the incoming signal has nothign to do with direction, it doesn’t matter) and the front and rear lights get swapped - plus the blue common is now on the “no connection” pin. The only thing that will happen is your loco will run in reverse, and none of the lights will work. No damage will occur to either the decoder or the loco. Add in the green wire and flipping the plug results in the connection to whatever function the green wire is connected to being reversed in polarity. Depending on what that’s actually connected to, it could possibly damage either the circuit or the decoder.
That’s why usually the green wire is left out and pin 3 of the 8 pin connector is not connected to anything.
–Randy