The parts diagram points to a DCC ADAPTER BOARD and a DCC JUMPER BOARD, but doesn’t say whether it wants an 8-pin, 9-pin, or 21-pin decoder. I don’t want to disassemble the locomotive to find out before I order the decoder because parts have a habit of escaping into the void when I leave a project half-finished for a while.
That’s all I need to know: do I order an 8-pin, 9-pin, or 21-pin decoder.
If you have the ID number (ATH-1234) or the railroad and engine number (CMQ 1006), you should be able to find the information on the Athearn website.
Is THIS the model you have?
I’ve dug into several Athearn locos and many have a ‘dual-connector’ motherboard that will accept both a NMRA 8 pin and a JST 9 pin decoder.
Using the JST 9 pin “I think” will give you more lighting outputs without hard-wiring the Function 1 and 2 (green and purple) wires.
Good Luck, Ed
Yes! That’s it! Mine is a different road name, but it sure looks like the same loco. Mine is a part # ATH-77665 Norfolk Southern Railway Heritage AC4400CW, engine number 8098. I can even give you the bar-code number on the box: 97534-77665.
So thank you! That’s just what I needed to know: 8-pin or 21-pin. If I can just yank out the blanking plate and plug in the decoder, that works fine for me!
That Train Control website showing exactly how to remove the body shell is a life-saver too. I never would have guessed you had to unscrew the couplers to get the body shell off…
Getting a sound decoder would be nice, but since I bought it used from eBay, I can live without all the bells and whistles (pun intended).
No, not 21 pin.
Your choices are only 8 pin or 9 pin JST connector.
Many decoders come with nine wires attached to a harness. You remove the harness by pulling it out with a bit of a wiggle, then the decoder can be ‘plugged’ in to that short ‘pigtail’ coming off the main board.
Here are some examples:
Good Luck, Ed
Thank you, Ed! You misunderstood. What I meant is that I just needed to know whether it uses 8-pin or 9-pin or 21-pin decoder. Now that I know it uses either 8-pin or 9-pin decoder, I know what to buy. I’ll prolly get that DP2X decoder which that TCS page suggested.
OK, but keep in mind if there are any ‘extra’ lights, besides the headlight and reverse light, the DP2X won’t allow them to function. Check to see if your AC4400CW has anything more than just the headlight. If not, sure, the 8 pin NMRA will work.
On the “8” pin decoder socked only 7 pins are used. One is a dummy. As I mentioned earlier, the 9 pin JST socket uses all 9 wires and allows four functions to be controlled, headlight, reverse light, function 1 and 2 which may be ditch lights, an oscillating light or number boards depending on your engine.
Regards, Ed
Thank you again. I’m not sure because my layout is DCC, so I can’t put it on the track yet to see what lights up. What specific decoder do you recommend?
It doesn’t hurt to have the ability to do a test run with a new engine on DC before adding the decoder. That way, you know there are no operating issues, and in this case, you can see if it has working ditch lights or something similar.
Any 8 or 9 pin decoder will work in the engine. Some decoders have more functions than others, you just need to review the decoder maker’s website. TCS decoders are easy to program, so would be a good choice.
BTW most all the diesels you buy are going to need you to take off the couplers to remove the body, it’s a pretty standard way of doing it. 