Bachmann Online Forum

Discussion Boards => HO => Topic started by: farrellrc on January 23, 2011, 11:47:19 AM

Title: DCC engine starts running on it's own!
Post by: farrellrc on January 23, 2011, 11:47:19 AM
My GP38-2 with DCC on board starts by itself and runs at full speed. I disabled the analog operation in the CV29 but it still does it. Could this be caused by the capacitors? What else can I do other than replace the decoder with NCE or Digitrax?
Bob
Title: Re: DCC engine starts running on it's own!
Post by: jbsmith on January 23, 2011, 11:50:49 AM
Maybe you have an HO Scale model train version of  "Christine" !  ;D  [a movie about this  guy and his car]

Could not resist.

Title: Re: DCC engine starts running on it's own!
Post by: farrellrc on January 23, 2011, 11:54:51 AM
I sure hope not! But, she was a beautiful car, 1957/58 Plymouth Fury, Red.
Title: Re: DCC engine starts running on it's own!
Post by: Pacific Northern on January 24, 2011, 10:17:33 PM
Quote from: Hunt on January 23, 2011, 12:51:01 PM
Runaway not caused by the capacitors.

Place the locomotive on the programming track and program CV 8 with 8 (if it is Bachmann decoder equipped). This probably will not help as a runaway is usually a faulty/damaged decoder.


When I added a Digitrax DCC decoder to a Spectrum 2-6-6-2 the engine would move on its own without turning the throttle. It was super erratic, the speeds alternated between slowand fast. Would not respond to direct as well.

Cut the capacitors, engine now runs fine. Super slow speed control, realistic top speed. Pulls all the cars I assign, without slipping.
Title: Re: DCC engine starts running on it's own!
Post by: Scott823 on January 25, 2011, 04:12:18 PM
Quote from: jbsmith on January 23, 2011, 11:50:49 AM
Maybe you have an HO Scale model train version of  "Christine" !  ;D  [a movie about this  guy and his car]

Could not resist.



HAHA! i just watched that movie!
Title: Re: DCC engine starts running on it's own!
Post by: Pacific Northern on January 26, 2011, 01:18:19 AM
Quote from: Hunt on January 24, 2011, 11:46:32 PM
Pacific Northern,
I am familiar with the circumstances you describe and a Digitrax decoder being corrected by cutting the capacitor across the motor circuit. In fact, slow movement on its own would have likely been corrected by just resetting CV29. The erratic speed removed by cutting the capacitor. This not the same as a runaway at full speed.


There was nothing slow about the 2-6-6-2, I placed in on the tracks and plugged in the EZ command and away went the engine. Did not even turn the throttle.