Is my decoder fried?

[goofymike01]

Here is the situation.  I am using a digitrax DH163D in a Athearn AC4400, I just plugged it into the 9 pin plug.  I can program the adress and the engine will go forrward and backward but it is jerky.  I am using JMRI and I try to read the decoder and it doesn't know the manufacture, I have other engines with the same model of decoder and JMRI has no problem seeing those.  When I go into the advanced programmer it shows my speed settings as a straight line at the bottom, I try to change them and it appears that I do in JMRI but when I run the negine I get the same results.  I run it back onto the programming track and read it again and evrything flatlines back out to where I found it.  I am also seeing many CV's set to 255, I know this is not right, also when I close out of JMRI it says that some stuff has not been written to the engine.  Your all probably wondering where the question is at this point.  Is my decoder fried or does JMRI have a problem with it?

[Johnnny_reb]

It sound like a bad decoder.

[locoi1sa]

     How did the loco run on DC? If it ran good than Try to do a reset CV8=8. Clean the wheels and check the 9 pin plug for any bent pins and not plugged in far enough.

  Pete
 

[jasperofzeal]

Do you have another decoder you can put into the AC4400?  If you do, try subbing a different decoder for the one that's giving you problems.  If you get the same results with the sub decoder, then maybe you have a defective circuit board in the engine.  If you don't have another decoder to try the subbing test, then maybe use another engine to test the problematic decoder.  If the test loco behaves like the AC4400, then the decoder may be bad, if not, then you may have a defective circuit board in the AC4400.  In which case you'd need to contact Athearn to replace the circuit board for you.

Now, if you have a bad decoder (which you can determine from the testing above), try resetting the decoder to factory settings (even if it is new), see what that does.  Hopefully someone here can eleborate on how to reset your decoder.  Still no go?  Then see if you can get a replacement decoder from where you bought it.  That's what I would do, good luck.

[goofymike01]

I tried what you mentioned above and it is the decoder, Thanks for your help guys.