# Questions about install and ditchlights



## I Am Fasha (Apr 2, 2013)

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Decoder install problem
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fngfashaToday at 8:43 AM
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First let me say thank you for the help that I know I'm going to get here! Please be patient with me as a lot of this is new to me and Im learning by feeling my way through it.

Here is the situation. I'm working on a Athearn Genesis SD-70M that came with some type of factory decoder. The owner sold it to a friend who has asked me to fix it. It came to me with the cab off and front headlight wires cut to close to reconnect. Same with the rear lights. It not has a Digitrax DH 165 AO decoder snapped loosely above the motor with no wires attached. 

I located and downloaded the manual for this decoder from here: http://www.digitrax.com/static/apps/products/mobile-decoders/dh165a0/documents/DH165A0.pdf

Since then I have been able to get the left and right track power hooked up from both ends of the loco. I have got the motor hooked up and the loco runs. I have tested the FOF + and FOF as well as the FOR and FOR+ tabs for the front and rear lamps and they work. Now I would like to make sure of the placement of wires for the ditchlights and Im close to being lost.

If Im looking at page 6 of the manual linked to this post above, do the ditch lights hook to F!, F2, F3 & F4 on this decoder? Lets start with that as the first question and go from there.


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## Southern (Nov 17, 2008)

No. wires form one ditch light go to the F1+ and one to the F1, You will need a resistor. the other ditch lighthooks to F2+ and F2.,


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## I Am Fasha (Apr 2, 2013)

Southern said:


> No. wires form one ditch light go to the F1+ and one to the F1, You will need a resistor. the other ditch lighthooks to F2+ and F2.,


Okay that is question one from the my Mentor, question two from Grasshopper. This F1 and F2 are the function keys on the throttle right?

Follow up question, I will need a resistor for each light correct?


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## Southern (Nov 17, 2008)

Question 1: yes and no. you can remap them.

Follow up question: yes and no. they can share on. but the the voltage must me dropped for each of the LEDs.


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## I Am Fasha (Apr 2, 2013)

Okay sounds good! I will get them installed and then come back for help with the remapping :smilie_daumenpos:


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## Southern (Nov 17, 2008)

start with very low voltage unless you like flash bulbs.


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## rrgrassi (May 3, 2012)

You can also have them flash when you press the horn button.

Listen to Southern, he is knowledgeable in this area. 

You can also get manuals from Digitrax and Soundtraxx. The CV's are different, but the idea is the same.


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## I Am Fasha (Apr 2, 2013)

Thanks for reply and info RR. But I am curious how to wire the two lights and use one resistor.


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## rrgrassi (May 3, 2012)

If you do that, they will work singularly, not independently. So, no alternating flash. Usually you want the resistor prior to the bulb or LED.


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## I Am Fasha (Apr 2, 2013)

And thanks to both of you. Follow up question. Looking over the paperwork for this decoder (DH165AO) second line under Features on first page has this: "Regulated Headlights: convenient no-resistor install of LEDs and lamps.". Am I understanding this to mean that I dosnt need to use a resistor?


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## rzw0wr (Aug 28, 2013)

Correct. No resistor needed.


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## rrgrassi (May 3, 2012)

I Am Fasha said:


> And thanks to both of you. Follow up question. Looking over the paperwork for this decoder (DH165AO) second line under Features on first page has this: "Regulated Headlights: convenient no-resistor install of LEDs and lamps.". Am I understanding this to mean that I dosnt need to use a resistor?


Yes, no resistor needed. You may have to program the CV, or it has a different connecting point with a resistor built into the decoder.


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## I Am Fasha (Apr 2, 2013)

Good info RR. Thanks for the reply!


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