Steps needed for the DZ125PS or DZ143PS decoder installation:
![](http://www.digitrax.com/static/apps/tsd/images/AtlasHH600a.jpg)
Remove couplers and carefully remove loco shell to reveal the 8 pin dummy (DC) plug.
![](http://www.digitrax.com/static/apps/tsd/images/AtlasHH600b.jpg)
Remove 8 pin dummy (DC) plug [picture shown with plug removed].
![](http://www.digitrax.com/static/apps/tsd/images/AtlasHH600c.jpg)
Plug in the DZ125PS or DZ143PS with orange wired #1 pin in pin with triangle marked pin.
![](http://www.digitrax.com/static/apps/tsd/images/AtlasHH600c1.jpg)
Detail of DZ125PS or DZ143PS with orange wired #1 pin correctly oriented.
![](http://www.digitrax.com/static/apps/tsd/images/AtlasHH600d.jpg)
Tuck decoder in cab area of loco, replace shell and reinstall couplers.