If you mean is there continuity between the power wire and ground, then there is not.
The fuel pump is not wired into the system yet if that makes a difference.
I have a D180 an AP74 and a GTR200 Garmin and am connecting everything up. The D180 install manual page 8-5 shows the center terminal of the variable resistor going to the intercom/audio panel auxiliary input. Where is this in my system?