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I have an MTH 30-20367-1 NS SD70ACe with a bad ditch light.  I ordered CE2000002 as shown in the parts list for the SD70, but what I received is different.  The original ditch light is a small chip led mounted on a tiny circuit board.  The part CE2000002 is a small led with pigtails.  It does not fit.  I looked at a few different units for the part (Premier SD70 and RailKing ES44AC) but there are none that show the correct part. 

Any ideas?

Tony V

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  • SD70ACe Ditch light: Top is original and bottom is from MTH service parts
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Also, I hate to see people go through a problem, go through all kinds of sourcing parts- only to find out that's not the problem.

A known issue I have seen is the lighting breakout board, the traces are thin and since it is a one sided PCB, pressure on the connectors can crack or rip a trace- especially these ditch lights.

Again, what can happen is, those plug in socket connectors on this breakout PCB are flexed or otherwise stressed. The tiny traces and the glue holding them to the PCB substrate then rips or cracks and no longer is the connector actually connected back to the PS3 PCB wiring.

I've had to jumper wire or repair the contacts on this breakout PCB, and then use superglue to lock the connector sockets and pins to the PCB as strain relief.

IMG_3090IMG_3092

Not sure if you tested the suspected failed LED with an LED tester or my favorite trick, a CR2032 coin cell.

The beauty of using the coin cell is, it self limits the LED current- no resistor required.

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Not sure if you tested the suspected failed LED with an LED tester or my favorite trick, a CR2032 coin cell.

The beauty of using the coin cell is, it self limits the LED current- no resistor required.

Actually, the reason the CR2032 coin cell doesn't smoke the LED has more to do with it's voltage than it's current capability.  It's 235ma far exceeds the 20ma operating current of most common LED's, however it's max voltage of around 3.3 volts serves to limit the actual LED current.

The green arrow is about at the 3.3 volt input voltage and the LED is drawing 10ma.

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@Vernon Barry  I tested by swapping the 2 ditch light connectors to see if the problem stayed or moved. In my case the issue stays with the failed ditch light (the other works regardless of the connector position on the board).  It actually appears to have a cold solder joint now that I have it out.  I may try to fix it but it is terribly small and the old eyes and not so steady hands may keep that from happening.  Of course it's already broke so I can hurt it...

Thank you for the options.  I think I will try big A first.  I only need 1 part right now so 1 led and shipping will be more than the 25 from big A.

@gunrunnerjohn Thanks for the tip.  I will try to repair what I have and now I have an easy way to test without reassembling everything and cussing when it doesn't work. :-)

Tony V

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