Dcc running backwards

[Rgreen1961]

Can someone please tell me what I have done wrong. When my trains all Hornby dcc and tts are running they stop and run backwards then go forward. Not happening at the same spot but, different places. Is it faulty chips (12 in total) or the controller ( have one and a spare. Does it with both)

[mjb1961]

Sounds like dirty track !!,,,give your track a good clean and then try ,,,

[Chrissaf]

The way you have worded your post infers that this odd event happens to all running locos simultaneously at the same time. Which would be a very strange event indeed.

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I take it what you meant to infer was that only one loco exhibits this behaviour at a time, but it could happen to any loco you have and not be confined to one particular loco or track location and is effectively a randomly timed event.

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Which inference is nearer your issue?

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EDIT: As mjb said above, dirty track and wheels is probably the prime candidate for further investigation.

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The theory of the principle is:

DCC commands are automatically repeated by the controller on a timed basis. Loco travelling forward, dirt causes the loco decoder to misinterpret the DCC signal and think it has been given a 'go backward' command. The loco goes into reverse and moves back to a part of the track where the repeated 'go forward' command is then correctly read by the decoder again. Loco then goes back to forward direction until this error happens again. It is a lottery as to where on the track this occurs as the 'timed' DCC command being read by the decoder has to coincide with the track conditions that affect the decoder DCC command reading.

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