Is Decoder Goosed?

[salmontrout]

Hi

I have a hard wired Ivatt 2mt 46521 which I was running on a test loop with select controller. Thought I would leave it to run for half an our or so as I had done with other locos which hadnt had much running on main circuit.  When I went back, it was stopped, derailed at power inlet track and controller was flashing 11.  Reset controller and put loco on track.  Immediately it took off in reverse without being called up  It was set to 01.  Totally unresponsive to controiller. Decided to reprogram it using elink.  When it read the decoder it came up with 115.  Reset it to 01 and then back on running track.  Again it immediately took of in reverse and is unresponsive to e link.

Suspect decoder gone but made have to do with CV 29 which I dont know how to work as yet.

Any help appreciated

[poliss]

What decoder is it? Did you reset the decoder? Usually done by entering 8 into CV8.

Are you using two, or four digit addresses? If two digit address and no complex speed curve etc. Then enter 2 into CV29. That will turn off DC running.

Never leave the room when running locos. They will notice and derail as soon as you leave the room. 😆

[salmontrout]

Thanks for quick reply

I dont know what decoder is used in the loco. Im using a two digit address.

To do what you suggest, do I go to locomotive setup in railmaster and just type these numbers into the relevant

 CV boxes.  Presumably this is when loco is on programming track

[poliss]

On the programming track, yes.

[salmontrout]

Sorry to be thick about this.  I put it on the programming track and then do I read the deooder byclicking the green tick or just put in the two values you have given me and click write button.

[poliss]

No need to read the value. Make sure you're writing to CV29.

[Fishmanoz]

Just to expand a little, what we think you are seeing is a problem called DC Runaway from the decoder getting a bad DCC signal due to something like dirty track, dirty wheels or pickups not sitting firmly against clean wheel backs.  When the decoder does this, it switches to DC mode and, given DCC puts full volts to the track at all times, the loco takes off flat out and can't be stopped without removing power.  The solution is to clean and adjust everything, then turn off DC running in CV29 as poliss has said so it can't happen again.

 

To write 2 into CV 29, follow the instructions in the manual for writing to CV29, RM having good inbuilt support for adjusting this CV.  And the 115 read you got is most likely telling you there was an error reading, not that this was the real value found.  Not surprising given you probably have cleaning and adjusting to do.

 

And the answer to your original question - no, the decoder probably not goosed.