The 16-port Data Link Connector on my 2004 Civic fails to power up OBD-2 readers. Using a DMM, I got these voltages on the pins:

Pin 7 - 14 VDC
Pin 9 - 4.8 VDC
Pin 14 - 4.9 VDC
Pin 16 - 0.37VDC

Notably, pin 16 is supposed to be the power supply for the OBD-2 readers (according to the pinout diagram at OBD II diagnostic interface pinout diagram @ pinoutguide.com).

On a (maybe) related note, my car's cigar lighter (aux power socket) has no power, and the radio is removed. I have removed fuse 18 and verified it good; I have verified power is available up to the fuse. I have verified the load and line side of the fuse receptacle are not grounded. I have done nothing with the under-hood fuse box.

I am at a loss for how to continue; I can't a schematic that shows where exactly pin 16 gets power from. I looked through the Civic 2001-2005 Sevice Manual; it makes several references to the 16p DLC, but never shows which pin is which.

Does anyone have any ideas, or perhaps a useful schematic? Thank you very much.