Two things come into play here, assuming the decoders are installed properly and the factory boards aren't defective:
One is that the default, from the factory, for non-sound DCC decoders is generally to have all the functions turned off. That's why your new installs don't have any of their lights illuminated.
The other is that a decoder will "remember" it's last state. Your used loco likely had the light function turned on the last time it was on a DCC layout. It "remembers" that (the same way the new decoders remember they're off), so it turns the light on when it gets power.
The exception, of course, is "analog conversion", which is on by default with Digitrax decoders. That's what allows your locos to run at all when they're on a DC track. However, once you convert your layout to DCC you will probably want to turn it off as it tends to contribute to runaway locos under certain conditions.
HTH,Steve
Hi all,
I am new to dcc and have fitted plug in /plug and play decoders 4 of my locomotives a six pin DZ125 digitrax decoder was fitted in a Kato class 66 european chassis, and a digitrax DN163KOa digitrax decoder in a Kato PA-1.
The two class 66 locos are new from Kato and run well although no lights operate on them, the PA-1 locos also new both run well enough but only one has lights working, i am at the moment on a DC set up to test these locos and would like to know why the lights do not function on them especially why only one of the PA-1's lights work.
I should add the decoder in the PA-1 that has a working light i bought second hand so is it a case of once i have my DCC system set up i can sort out the light function on the control as this may have been done by the previous owner of the decoder.
Any help would be appreciated.
Thanks.