# Installing LED Headlamp in Athearn Blue Box GP Locomotive



## DavefromMD (Jul 25, 2013)

I've been toying with the idea of replacing the cab light in a BB GP diesel aand installing an LED headlight. How do you go about that? WHere do you attach the LED wires to?


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## mopac (Feb 24, 2011)

I am guessing you are running DC. You can attach LED leads to same thing that powers the bulb. The frame and that copper strip on top. You must use a resistor inline with one of the LED leads. If not you will blow LEDs as fast as you can install them. Try a 1000
ohm resistor.

LEDs are polarity sensitive. If it does not work switch the leads.


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## Grabbem88 (Feb 24, 2012)

Polarity leads are important but make sure if you do rear make it directional.

I received some LEDs from Sean that fit perfect snug in the place of the BB lenses if you want to do it that away..


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## DavefromMD (Jul 25, 2013)

What size LEDs?


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## Grabbem88 (Feb 24, 2012)

2mm LEDs


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## DonR (Oct 18, 2012)

Dave

As the guys have noted, you'll want to have your LEDs directional...
headlight/forward back/backward. The LONG lead of an LED
is for Positive...So connect that, thru the resistor to positive
feed when set for forward...inverse for the backup LED. If 1,000
ohms makes LEDs too dim, try a 470 ohm.

Don


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## rrgrassi (May 3, 2012)

Miniatronics Yeloglo sends the 470 ohm resistors with the LED's.


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