On Sat, 23 Nov 2013 17:32:11 +0000, Danny D'Amico wrote:

Right now, I'm trying to figure out why the power supply board
has 0 volts across the PWR and GND pins, even with 13 volts at
the inputs.

I just realized, that's *not* a power supply board!
http://farm6.staticflickr.com/5536/1...f98f0bb4_o.gif

It says it's a "D135A Low Battery Disconnect", part number
79-04360401 (where the last 4 and last 1 might be another digit).

Googling, I find these datasheets:
http://resource.boschsecurity.com/do...2548187915.pdf
http://www.boschsecurity.com.br/_arc...on_0910_en.pdf

Which say:
"The D135A works with compatible control panels to protect the
battery from deep discharge in the event of an extended AC
power outage. Disconnects the control panel from the battery
when the battery level drops to 9.5 VDC."

I find an installation guide here, which explains that the sticky tape
is because the module is supposed to be stuck onto the top of the battery:
http://tinyurl.com/p74he4t