Need help with 1996 Airbag code/light

[St.rAnger96]

Having a hard time tracking down why my airbag light just started flashing at me.

I've got a 1996 XLT with a 3.0/automatic with 140k.

Just yesterday when leaving work my airbag light started flashing at me - one flash, pause, two flashes, repeat. Code 12. Low voltage?

Well my battery is just over a year old, and has good standing voltage and tests as good with a snap on battery tester.
My alternator is older, but charges at 14.5. Tested with a multimeter, a schumacher battery charger and a snap on charging system tester. RPMs raise the charge rate, and it never drops below 13.5 while driving (verified with obd scanner connected while driving).
All my fuses in the side panel are good.
Gauge in the dash shows normal middle of the gauge charge rate.

Where else should I be looking for this code? Is there a common/known culprit that ISN'T a battery or alternator?

Where is this Airbag light sensing voltage exactly?

 

[St.rAnger96]

UPDATE
after using a different scanner and viewing individual systems I do have two codes present. Not sure why they didn't pop up on the other, more advanced ($$$) scanner.

I've got B1913 and B1867. Airbag short to ground and battery low voltage. I guess I'll start testing wiring and looking at diagrams.

 

[sgtsandman]

UPDATE
after using a different scanner and viewing individual systems I do have two codes present. Not sure why they didn't pop up on the other, more advanced ($$$) scanner.

I've got B1913 and B1867. Airbag short to ground and battery low voltage. I guess I'll start testing wiring and looking at diagrams.

The battery code might be an easy one. How old is the start battery and what voltage is it putting out after the truck has been sitting a while. From memory, at 12.4 volts, it's time to replace the battery.