View Full Version : Help with Atlas Silver C40-8CW HO w/Tsunami Install

02-14-2011, 06:47 PM
Hey guys,

Got a TSU-1000 decoder and installed it in an Atlas Silver C40-8CW I got a couple weeks ago. Got both speaker wired up, great sound.

I tested it, got horn, bell, sound, BUT...no lights.

I connected it with an 8pin plug directly to the Atlas board. I saw the light contact plates down by the ditch lights and thought that might be the linch-pin to getting the lights to work. So I put the shell back on and they still dont work.

All the pins are in on the 8 pin plug. Everything seems snug on the Atlas light board. This is a NIB New, old stock, never been opened locomotive.

Any ideas???

02-14-2011, 11:19 PM
This is just a guess, as I don't do diesels. Could the plugged in decoder be interfering with those contacts? It would seem that if the decoder interferes with the common contact for the lights, they will not work. The only other guess would be if the lights are LEDs, they only require 1.5 volts, whereas the tsunami decoders have 15~ volts for lights. They could have been burned out.

02-15-2011, 04:43 AM
I dont think the plug is interfering with the light board connections. The plug is seated well, and has good contact with the 8 pin connection.

Also, I left in the original Atlas light board and connected the Tsunami thought the light board. The Atlas loco's instructions indicate they are 1.5v lights.

Im going to unplug the decoder today and re-install the jumper to see if I can get the lights to work by DC today and then go from there.

02-15-2011, 07:08 AM
Alright Guys I got it fixed.

But the solution wasnt at all what Ive ever seen before. It turns out some of the Atlas locos have had this issue.

I put in a 8 pin extender to make sure all the pins were making solid contact. That got the lights to work. But then the engine and lights were running backwards from what was requested; ie REV was FWD and vice versa with corresponding lights.

Now normally, youd think, youve installed the plug backwards, just rotate it 180 degrees and viola...but that would be incorrect.

Turns out that in some of these Atlas engines, you have to program CV 29 to 39 to get correct engine and lighting direction.

In over 20 decoder installs, I have never witnessed this before. Very interesting.

Well now, I have a nice running and sounding Conrail C40-8CW.

thanks for reading and your help. Thanks for google searches too.


02-15-2011, 08:05 AM
And another question...

Im trying to get the ditch lights to work independent of the headlight. Ive installed the TSU 1000 version of the tsunami and added a 8pin to 9pin Digitrax harness for easy installation. I have a green wire and a purple/violet wire left over for functions 5 and 6. The other 7 wires are left attached to the 8 pin harness and plugged into the Atlas light board.

There are contact points for the ditch lights down by the nose that have ad red and white wires that run from there to the light board. Should I cut those and splice in to the green and violet wires? The tsunami directions say the brown wire is function 5 but off the Digitrax harness I have a green and violet/purple wire remaining. Looks to me I could solder the green onto the remaining position of the 8 pin harness and get control of FX 6 that way.

Anybody have any ideas or have done this before? Searches on here, google, and youtube dont turn up much. Again, this is for an Atlas Silver with a TSU 1000 Soundtraxx Tsunami added via a 9pin to 8 pin harness.



02-15-2011, 12:23 PM
Alright guys,

I was able to figure this one out too. Here's how you wire ditch lights on the bulb equipped dcc ready Silver Series Atlas for a Soundtraxx Tsunami:

You run the cut the black wire from each ditch wire light and solder a wire connecting them to the green and violet wires from the decoder (FX5 and FX6). The red (common) other wire from the ditch light is fed from the Atlas light board thru the 8 pin plug via the blue wire (common) of the decoder. Then its just a matter of programming FX5 &6 to the respective ditch light ie CV51 to 41 CV52 to 57.


02-15-2011, 01:18 PM
Brad, why did you decide to not use board replacement decoder instead of the generic?

02-15-2011, 01:59 PM
Brad, why did you decide to not use board replacement decoder instead of the generic?

I just wanted to pay the extra $15...:D

Just kidding of course...

When I popped off the top of this loco I was like "There's alot of wires in there..." More so than an Athearn or Athearn Genesis or Kato. So I thought by just doing the TSU board and attaching a 8pin plug to it, it would be an easier intall than the board replacement. Im not sure if it was...the ditch lights kind of thru me for a loop but it all worked out in the end.

I usu do use the board replacements in the Athearn Genesis and Kato locomotives as they are pretty straightforward and $15 cheaper.


02-15-2011, 03:43 PM
The board replacement may or may not fit in the Dash 8. I know for sure that the board replacement decoders do not fit in the Atlas geeps with the A-frame speaker mount.

If you get the TSU-1000 (No AT or GN) and pull the 9-pin JST harness off, then plug in a 9-pin harness with an 8-pin plug and a loose purple and green wire on the other end. Plug in the 8-pin plug, then trace the wires to the ditch lights.

The ditch lights are hooked into the headlights. Find the NEGATIVE wires to the ditch lights. The ditch lights are wired in parallel with the headlight so trace the positive from the socket. The wires are color coded red and black. Red is one polarity while black is the other one. (I don't remember which is which).

Clip the two negative wires to the ditch lights and wire them to the green and violet wires. Program the CVs and you're all set.

02-15-2011, 04:07 PM

Hey, that's exactly what I ultimately did. I guess I wasnt too clear about that in my last post. I was also a little concerned whether the board replacement for a "AT" board would fit, so that was another reason why I went with the TSU board.

Anyhow, it all ended up well. I am very happy with it and well into applying a NS Patch to the Conrail paint. Ill prob post some pictures next week in the Locomotives forum/Showin Off forum.

Take care,


02-15-2011, 04:26 PM
I have a Conrail Dash 8-40CW that I wanted to do the same to, but I never got around to doing it.

02-15-2011, 04:43 PM
Well, if you ever get around to it, just search for this thread...

If I knew what I was doing (we all know how every sound install can be alittle different), it wouldve been like a 1 hour project tops...

Take care,


02-15-2011, 04:45 PM
I'm thinking about selling the engine. I don't think I will add sound to it though.

02-15-2011, 07:10 PM
You shouldnt have any problem selling it, they are pretty sought after. Btw, you prob already know, but Atlas is coming out with a release of these engines again, just announced this month.