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Locomotive direction issue

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  • Member since
    July 2006
  • From: Bradford, Ontario
  • 15,797 posts
Posted by hon30critter on Saturday, March 3, 2012 11:56 PM

OilJunkie

Perhaps you missed Ken's posts, but he seems to have answered your question. Please let us know if he was right!

Dave

I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!

  • Member since
    February 2007
  • From: Christiana, TN
  • 2,134 posts
Posted by CSX Robert on Saturday, March 3, 2012 10:35 PM

Lake

Randy, he stated that it does not happen with any of his other engines.

If it was the UT4 then would it not do this with the other engines?

I don't believe Randy was replying to the original poster but instead to the post immediately before his.

  • Member since
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  • From: Clearlake, California. USA
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Posted by Lake on Saturday, March 3, 2012 9:14 PM

Randy, he stated that it does not happen with any of his other engines.

If it was the UT4 then would it not do this with the other engines?

Ken G Price   My N-Scale Layout

Digitrax Super Empire Builder Radio System. South Valley Texas Railroad. SVTRR

N-Scale out west. 1996-1998 or so! UP, SP, Missouri Pacific, C&NW.

  • Member since
    February 2002
  • From: Reading, PA
  • 30,002 posts
Posted by rrinker on Thursday, March 1, 2012 5:18 PM

 It's the toggle direction switch ont he UT4 - if the one brief "direction change" command gets missed, the loco ends up runnign the same way rather than changing direction. I've seen this happen at the club runnign on radio throttles. Never seen it happen with a DT40xR or D, only the UT4R/D's.

            --Randy


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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  • From: Mpls/St.Paul
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Posted by wjstix on Thursday, March 1, 2012 5:06 PM

I've had a similar problem once in a while with various engines when operating my layout using my Digitrax UT-4 in wireless (infrared) mode. Once in a while I'll have an engine going forward, reverse direction, and when I put the power to it, it goes forward again. Sometimes bringing the engine to a full stop before reversing seems to help.

It's apparently related to the signal getting scrambled somehow in the infrared. Never happens when I've got the UT-4 plugged in, or using my Zephyr's controls.

Stix
  • Member since
    April 2007
  • From: Clearlake, California. USA
  • 869 posts
Posted by Lake on Sunday, February 26, 2012 12:42 PM

I have the Super Empire Builder with the DT400R radio throttle same system as you have As I stated in my first post the decoder is is what is bad not your system. If the system works on other decoders then it is not as David states your Super Chief or throttle. Digitrax had a batch of the DN163KiB decoders, and the problem is known by Digitrax. They will replace it.

Ken G Price   My N-Scale Layout

Digitrax Super Empire Builder Radio System. South Valley Texas Railroad. SVTRR

N-Scale out west. 1996-1998 or so! UP, SP, Missouri Pacific, C&NW.

  • Member since
    December 2004
  • From: Bedford, MA, USA
  • 21,483 posts
Posted by MisterBeasley on Sunday, February 26, 2012 11:06 AM

That is the kind of behavior I'd expect from a mechanical problem.  It doesn't mean it's not the decoder, but I'm leaning mechanical at this point.  Is this a new engine, or one that's been broken in for a while?  If you can get it running in reverse, let it just run around for a half-hour or so.  If it's easy to get the shell off, blow some air into the gears.  There may be a particle of junk in there you can dislodge.

You can test this with a meter, if you have one.  Select AC Amps, and put the meter in series with your track, so that the current has to pass through the meter to get to the track.  (You measure voltage in parallel, but current in series.)  Run the engine in forward and note the current draw.  It should be around 100-200 milliamps.  Now, try the engine in reverse.  If it goes nowhere, but you have the same or more current, then the motor is trying to run but it's binding, a sure sign of a mechanical problem.  If, on the other hand, there is no significant current in reverse, then the decoder is probably not sending anything to the motor.

It takes an iron man to play with a toy iron horse. 

  • Member since
    December 2010
  • 17 posts
Posted by OilJunkie on Sunday, February 26, 2012 9:43 AM

So when it goes into reverse the rear cab light does come on, and there is no movement at all from the locomotive even when I turn the throttle up to say "20" on the controller.

Then when I switch the direction back without turning the throttle down, the rear light will stay on in about the same time it would take for the momentum to stop for the engine.  Then the front headlight will come on and the engine will start moving forward.  

  • Member since
    December 2004
  • From: Bedford, MA, USA
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Posted by MisterBeasley on Sunday, February 26, 2012 9:18 AM

A bit more information, please.  What exactly do you mean by "won't go in reverse?"  When you put the engine in reverse, does it move forward, or does it not move at all?  Also, what happens to the lights when you put it in reverse?  Does the rear headlight come on, or does the front one stay on?

If the problem is motion only, you could have a mechanical binding problem in the gears.  It might not be the decoder at all.

It takes an iron man to play with a toy iron horse. 

  • Member since
    December 2010
  • 17 posts
Posted by OilJunkie on Saturday, February 25, 2012 9:57 PM

Digitrax Superchief to be exact with the wireless controller.  And again I have only the one throttle for the whole system.

  • Member since
    December 2010
  • 17 posts
Posted by OilJunkie on Saturday, February 25, 2012 9:46 PM

Digitrax.

One throttle only.

 

  • Member since
    December 2010
  • 17 posts
Posted by OilJunkie on Saturday, February 25, 2012 9:35 PM

DCC system is good.  I only have one throttle controlling the loco.  I have 15 other locos and no problems.  I will have to check the decoder and the contacts to see if I have a possible short.

  • Member since
    December 2010
  • 17 posts
Posted by OilJunkie on Saturday, February 25, 2012 9:05 PM

A Digitrax DN163K1B drop in decoder.

  • Member since
    April 2007
  • From: Clearlake, California. USA
  • 869 posts
Posted by Lake on Saturday, February 25, 2012 7:48 PM

I have two of the same engine and had the same thing happen. It was the DN163K1B decoders that were bad. So I sent the decoders back to Digitrax for replacement. Works perfect now.

Cutting the hole in the shell under the fan air intake for the LED to clear was needed to have the shell go all the way on after the decoder is installed.

Ken G Price   My N-Scale Layout

Digitrax Super Empire Builder Radio System. South Valley Texas Railroad. SVTRR

N-Scale out west. 1996-1998 or so! UP, SP, Missouri Pacific, C&NW.

  • Member since
    December 2011
  • From: Bradford County, PA
  • 1,319 posts
Posted by Lehigh Valley 2089 on Saturday, February 25, 2012 7:29 PM

Wow, that will be one tough nut to crack.

My guess is that there might be something wrong with the decoder, allowing the engine to run, but once in a while, not allow the engine to run in one direction. Maybe it's just installed wrong.

However, the first question should be, what kind of decoder is it (AMD4, M1, Lenz Mini Silver Series)? Is it factory installed, or did you install it yourself. If you installed it yourself, what type of decoder is it (drop in, plug-and-play, hardwired)?

Did you do a factory reset?

If you don't think the decoder is installed incorrectly, if it's the wrong decoder, if it's the right type of decoder, and you did a factory reset, just get a new decoder. It's not worth getting ticked off about, so if you tried all of this, cut your losses and get a new decoder.

The Lehigh Valley Railroad, the Route of the Black Diamond Express, John Wilkes and Maple Leaf.

-Jake, modeling the Barclay, Towanda & Susquehanna.

  • Member since
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Locomotive direction issue
Posted by OilJunkie on Saturday, February 25, 2012 6:26 PM

I have a Kato N Scale AC4400CW and I am having a problem with the decoder.  I have programmed it will work fine.  However once and a while the loco will only go forward and not reverse.  So I have tried resetting the decoder, put the CV's back to where I had them and it works for a bit and then starts going in only the one direction.  Any help would be greatly appreciated!

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