# Digitrax SDN136PS in GE 44 ton dual motor engine



## graywolf06 (Aug 14, 2019)

I am installing the the SDN136PS in the 44ton and plan to use LEDs for lighting. I know I need to add a 1000 omh resistor for the LEDs but this is my question. The blue wire from the decoder is the positive common --- the white wire is the headlight and the yellow the rear light. Can I just add the 1000 omh to the blue wire and thus satisfy both the front and rear LED's needs since only one light is on at a time? Also if I need to install the resistor on each does it matter if it is installed it on the positive or negative? Thanks for your input. Paul


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## Dennis461 (Jan 5, 2018)

graywolf06 said:


> .. Can I just add the 1000 omh to the blue wire and thus satisfy both the front and rear LED's needs since only one light is on at a time? Also if I need to install the resistor on each does it matter if it is installed it on the positive or negative? Thanks for your input. Paul


If you are certain that you will never run both lights on, then put resistor in BLUE wire. 
The resistor cold go in either wire to the LED.


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## graywolf06 (Aug 14, 2019)

The problems continue. I never got around to hooking up the lights because the engine didn't work with the decoder in DCC. It ran in DC. There was power getting to the decoder, 14.5 v on the AC scale but nothing coming out of the decoder in DCC. I explained this all to Digitrax and they sent out a replacement that I got yesterday. Installed the new 136 today and the same result. I tried all different addresses ---obviously 03--- Nothing. I tried a CV8 reset to 8 and still nothing. The engine still runs in DC thru the decoder. Digitrax wants me to send it back again. The decoder is spending more time going back and forth to Florida then me trying it. I was wondering it I should try to see if I can run it by itself out of the engine. Will this work? I have a spare motor and I could attach the gray and orange wires to it and then attach the black and red power feed wires to the track with jumpers and power up the Powercab on address 03 to see if the motor turns. BTY I don't have any lights hooked to the blue & white or the blue & yellow wires--- is that OK? Paul


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## graywolf06 (Aug 14, 2019)

I need help!!! I purchased SDXH166D Digitrax decoder to use on a FM diesel. The problem I am having is the same as the problem I was having with the SDN 136 as mentioned above. The engine will work in DC but no response at all in DCC. I am using a NCE powercab and tried both on the program track and the main line. I am trying to address 03 but there is no output indicated coming out of the decoder. There is 13.45v coming off the wheel pickups indicated at the red and black wires feeding the decoder, but nothing coming out of the decoder to the motor. I tried a CV8 to 8 reset and still nothing. As mentioned the engine runs on DC and even emits some engine noise from the speaker. The engine does work with an old motion only Bachmann decoder that I salvaged from a GE 70 ton. The interesting thing is that I put a 166 in that engine and a 136 in each of 2 Doodlebugs and they all work. I am pull out what little hair I have. I need help!!! Paul


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## graywolf06 (Aug 14, 2019)

Update!!! I managed to get the engine running by programming the engine number 926 as the address. The horn blows and the bell rings and it goes thru a startup sound sequence. The other minor functions work also. The engine will not respond to address 03. I am also able to program CV's on address 926 only. Any thoughts re 03???


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## DonR (Oct 18, 2012)

If your loco responds to 926, you have changed
it's address from 03...thus it will no longer
respond to 03. That's the way it should be. All
new locos and new decoders arrive as 03. It
is advisable to change to a different number as
soon as possible. By doing a RESET you can
restore 03, but there is no reason to do that if
the unit is working properly as 926 and that is
the number you wish for it.

Don


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## graywolf06 (Aug 14, 2019)

Thanks Don,understood, just can't understand why it didn't respond to 03. Going to go back to the 44 tonner with the 136 and see if I have to change the address. BTW I have 14.62 volts on the AC scale on the program track. At first I thought it might be insufficient voltage causing the problem. Also when you don't call up "program track" on the NCE Powercab the track I am using just acts like its the mainline. Had a difficult time convincing the people at Digitrax that what I just said was so. They kept saying you are on the program track and I said not unless I call up program track on the Powercab.


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## MichaelE (Mar 7, 2018)

It might not have responded to 03 address because that's not what was programmed. That's all I can think of.


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## graywolf06 (Aug 14, 2019)

Update!! Reinstalled the SDN136PS on the 44 tonner and tried using address 03 again. No response. Changed the address to the engine's # 51 and it all works. Bell, horn all F functions. I am baffled what gives with these Digitrax decoders? They say they are delivered with 03 address but they don't work. Even with the SDXH166D I used on the FM diesel.


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## Lemonhawk (Sep 24, 2013)

What do you mean by "you changed the address to the engine number"? You mean you programmed the decoder to that address and it all worked? Or did you just change the throttle to use that number loco and it all worked. If the latter, what are the chances of Digitrax delivering a decoder preprogrammed to your engine number?


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## graywolf06 (Aug 14, 2019)

Lemonhawk, no I tried 03 since new decoders are supposed to be delivered that way and nothing happened. I then programed the decoder with the engines # 51 and everything works.


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## Lemonhawk (Sep 24, 2013)

So some how it came programmed to an unknow address, how strange.


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