How to disconnect GND, with Pic

[amgen]

<img id="vbattach_6383" class="previewthumb" alt="" src="http://www.picbasic.co.uk/forum/attachment.php?attachmentid=6383&amp;stc=1" attachmentid="6383">

[davewanna]

Dave,

All earths should be disconnected, there are no external sources of power or earth currently.

amge,

I'm not sure I fully follow your circuit there. looks like the buttons are from 12V to a FET gate, and not to the pic. I need the buttons to turn the pic on, and give an input signal to the PIC at the same time. I will have a go at attaching my circuit.
Again, excuse the amateur..

[davewanna]

I have made the problem a lot better by adding a 200uF cap across the output of the regulator. My theory is that keeps the PIC alive long enough to drive the FET completely off. The fault happens less often now, but it still happens.