HO Scale SD40-2 Santa Fe diesel locomotive Item #60901

[AMD103]

I purchased this diesel locomotive several years ago. Just this past week, I gave it
a test run. Unfortunately, it only ran in reverse in reference to the cab; no lights
either direction. I'm running with a MRC Controller.
Any suggestions as to where I start trouble shooting
Thanx in advance...

[jbrock27]

Do you have the ability to take the shell off?  And to be sure it is not a problem with the controller's direction switch, have you run another loco using it, in forward and reverse?

[jward]

or, if you don' have another locomotive, turn this one around and see if it goes forward now. if it does, the problem is your power pack. if it still only runs reverse the problem is the locomotive.

[AMD103]

Good Evening JWard & JBrock27,
Thank you for your input to my problem, I have learned since the original post, the locomotive moves AOK[forward/backwards] in a different layout environment. As I mentioned earlier, unit did not have any operating Head/Rear lights. I removed the shell and inspecting the light/motor assembly, I did not see anything out-of-place. The markings on the board are as follows:
   H601X#PCB01, REV-A   06/04/04
Does anyone know if this is the latest light/power motherboard for this diesel locomotive???
Does anyone know if there's a schematic available for the diesel locomotive???
Does anyone know if there's a more recent decoder available for this diesel locomotive???
Thank You in advance for all/any information anyone can provide.
Respectfully
Robert[Bob] E. Cronan

[jbrock27]

You're welcome Bob.   

Can we assume then, you have no other locos?

[jward]

this hasn't been asked before, but is this a dcc or analog locomotive? which mrc controller are you using? it is sounding like the issue is with the controller not the locomotive.

btw, you can make a polarity sensitive test light by soldering a bi-colour led (two lead version) to a 1000 ohm resistor. cut a pair of test leads in half and solder one half to each end of the led/resistor combo. with dc power on the rails, and this rig clipped to each rail, you should be able to make the led change from red to green and vice versa by simply flipping the direction switch on your controller.

[jbrock27]

is this a dcc or analog locomotive? which mrc controller are you using?

Good questions  but, not sure I would go through the trouble of making such a device as that requires tools and supplies Bob may not have.  I will go out on a limb and say he likely does not.  Also given Bob's initial question, I would not assume he can concoct such a device.  Plus, if he did not already have a digital multi meter, it would be a good idea for Bob to get one.

[WoundedBear]

Most multi meters are polarity sensitive. When you see a negative sign (-) beside the voltage value, it means you have the red lead connected to ground. If you switch the leads, the negative sign goes away.

When testing a polarity-changing switch with a multi meter, just connect your leads and watch for a negative sign to appear and/or disappear, when you flip the direction switch.

Sid

[AMD103]

Good Afternoon Gentlemen,
Thanx for following me thru this journey of trying to get this SD40-2 Santa Fe diesel into service.
Checking/double-checking the MRC Controller by using a Volt/Ohm Meter along with an RRAMP Device from Tony's
Train, I assured my self that the controller is not at fault. The engine goes forward/backward in both DC & DCC...
Now I would like to get the Head/Rear lights to work. At the expense of saying this again, is there a schematic of
the motherboard available for this unit??? If I understand the markings on the current board, this board was produced
06/04/04 which to me translates to a very old board. Have any of you gentlemen trouble-shot a lighting problem on
Bachmann engine(s) Is there a real-life decoder available for this unit??? Is a programming folder available for this
unit or should I assume NMRA Standards could/would give me the answers???
Once again, Thanx for all your assistance.
Respectfully
Robert[Bob] E. Cronan

[Hunt]

Bob,

I no longer have my technical notes for the Bachmann HO SD40-2 DCC On Board.  However,  Click Here   use this for the decoder supported CVs information.

Look into a  NCE Silent Running motor drive BACH-DSL version 3.6 decoder  (less than $20) as a replacement.

[jward]

note that the bach-dsl decoder is not a plug n play. you will need to hard wire it into your locomotive. that said, it is one of the easier hardwire conversions.