pixels staying on, only 1 prop

[LangfordDave]

Hi, kind of a weird situation that I can't find an answer to anywhere.  I'm using a Pixie 16, this is my second year with it.  No major issues so far, I was successful in adding power injection points throughout my props last year and they all worked just fine.  This year I've had my show up and running for 1 week with no problems, but last night one of my props was still lit up after the show ended for the night, but only in the power injected pixels.  I use a different power supply from the controller for PI, so the 12v is cut between pixels 50 and 51, and the power is injected at the end (pixel 100).  This particular power supply is not on the same timer as the rest of my show, so power to it is never cut off.  But that has never been an issue before.  Even now if I power cycle it without the show running, those pixels come back on in the same last pattern as when they shut off.  When the show is running, those pixels behave normally.  I did find some water in the connection leading to pixel 1, I've since dried it out and added some dielectric grease.  But I imagine if it's a water problem at that point, it would affect the entire prop, not just the second half.  The connector between PI and pixel 100 is completely dry.  Any ideas?  (I could put this power supply on a timer and nobody would ever know there was an issue, but this seems like a band aid solution...I'd like to get to the root of the problem).

Thanks in advance for any insight!

[TheDucks]

Make sure your show turns them OFF befor powering down the show controller.

Make sure Both supplies have a good connection tied between the - terminals (that is a reference for both power and data. It needs to be the same (circuit wise)

[LangfordDave]

Show definitely is set to turn all off.  I'll double check the grounds, thanks for the suggestion